here is a constant flux of power  between the gods and demons. They  are always in conflict with each  other similar to the cycle of day and  night. It is actually a natural  phenomenon which cannot, nor should not  be stopped. This conflict between  good and evil causes the revolution  of time and events and the churning  of history. 
The current war however is somewhat different than any  in history  and the demons plan to make a lasting effect with  the current scheme.
Since time immemorial the key has been the earth  realm. The demons  suffered a great deal as a result because the earth  realm happens to be  inhabited by humans.
Humans are descendants of the  gods themselves and as a result are inclined to worship them.
When yajna (sacrifice/worship) is performed on the earth planet the  Devas are empowered and able to keep the delicate balance of nature  intact.
When that is not allowed and Dharma is not followed then the demons gain more and more sway.
Cows and priests are always the target because those two things are  vital. The cow gives dung and ghee which are both used as fuel in sacred  fire.
Therefore demons endorse cow slaughter as a means to put an end to  this. They also try their best to corrupt and disrupt the works of  devotees.
Hiranyakashipu and other demons have always thought that Vishnu was  like the other Devas and if they could kill all the Vaishnavas they  could weaken him to the point of killing Him.
This is why he killed many Vaishnavas and would disturb sacrifice.
Whatever force in this world which has an aim to destroy temples and  the worship of Vishnu ultimately has its agenda being directed by  demons.
Other more vague concepts of "God" make no explicit attack, rather they attack by trying to corrupt the truth of Personalism.
Here are some examples from Srimad Bhagavatam from the lips of Hiranyakasipu himself, spelling it out in black and white:
SB 7.2.10
While I am engaged in the business of killing Lord Vishnu, go down to  the planet earth, which is flourishing due to brahminical culture and a  kshatriya  government. These people engage in austerity, sacrifice,  Vedic study,  regulative vows, and charity. Destroy all the people thus  engaged!
PURPORT by Srila Prabhupada:
Hiranyakasipu's main purpose was to disturb the demigods. He planned  first to kill Lord Vishnu so that with Lord Vishnu's  death the demigods  would automatically weaken and die.
Another of his  plans was to disturb the residents of the planet  earth. The peace and  prosperity of the residents of earth, and all the  other planets, were  maintained by the brahmanas and kshatriyas.
The Lord says in Bhagavad-gita (4.13),
catur-varnyam maya srishtam guna-karma-vibhagasah:
"According to the three modes of material nature and the work  ascribed  to them, the four divisions of human society were created by  Me."
On all  the planets there are different types of residents, but the  Lord  recommends, referring especially to the planet earth, which is  inhabited  by human beings, that society be divided into four varnas --  brahmana, kshatriya, vaisya and sudra.
Before the advent of Lord Krishna  on this earth, it is understood that the earth was managed by the  brahmanas and kshatriyas.
The duty of the brahmanas is to cultivate samah (peacefulness), damah  (self-control), titiksha (tolerance), satyam (truthfulness), saucam  (cleanliness) and arjavam (simplicity), and then to advise the kshatriya   kings how to rule the country or planet.
Following the instructions of  the brahmanas, the kshatriyas should  engage the populace in austerity,  sacrifices, Vedic study and adherence  to the rules and regulations  established by Vedic principles.
They should also arrange for charity to  be given to the brahmanas,  sannyasis and temples. This is the godly  arrangement of brahminical  culture.
People are inclined to offer yajna because unless sacrifices are  offered there will be insufficient rain (yajnad bhavati parjanyah [Bg.  3.14]), which will hamper agricultural activities (parjanyad  anna-sambhavah).
By introducing brahminical culture, therefore, a kshatriya government  should engage people in performing yajna,  studying the Vedas and  giving charity.
Thus the people will receive  their necessities for life very easily, and there will be no  disturbances in society.
In this regard, Lord Krishna says in Bhagavad-gita (3.12):
ishtan bhogan hi vo deva
dasyante yajna-bhavitah
tair dattan apradayaibhyo
yo bhunkte stena eva sah
"In charge of the various necessities of life, the demigods, being  satisfied by the performance of yajna  [sacrifice], supply all  necessities to man. But he who enjoys these  gifts, without offering  them to the demigods in return, is certainly a  thief."
The demigods are authorized supplying agents who act on behalf of the  Supreme Personality of Godhead, Vishnu.  Therefore, they must be  satisfied by the performance of prescribed  yajnas.
In the Vedas, there are different kinds of yajnas prescribed for   different kinds of demigods, but all are ultimately offered to the   Supreme Personality of Godhead.
For one who cannot understand what the  Personality of Godhead is,  sacrifice to the demigods is recommended.  According to the different  material qualities of the persons concerned,  different types of yajnas  are recommended in the Vedas.
Worship of  different demigods is also on the same basis -- namely,  according to  different qualities. For example, the meat-eaters are  recommended to  worship the goddess Kali, the  ghastly form of material  nature, and before the goddess the sacrifice of  animals is recommended.
But for those in the mode of goodness, the  transcendental worship of  Vishnu  is recommended. Ultimately, all yajnas are meant for gradual  promotion  to the transcendental position. For ordinary men, at least  five yajnas,  known as panca-mahayajna, are necessary.
One  should know, however, that all the necessities of life that  human  society requires are supplied by the demigod agents of the Lord.  No one  can manufacture anything.
Consider, for example, all the eatables of  human society. These  eatables include grains, fruits, vegetables, milk  and sugar for persons  in the mode of goodness, and also eatables for the  nonvegetarians,  such as meats, none of which can be manufactured by  men.
Then again, take for example, heat, light, water and air, which are   also necessities of life -- none of them can be manufactured by human   society. Without the Supreme Lord, there can be no profuse sunlight,   moonlight, rainfall or breeze, without which no one can live.
Obviously,  our life is dependent on supplies from the Lord. Even for  our  manufacturing enterprises, we require so many raw materials like  metal,  sulphur, mercury, manganese and so many essentials -- all of  which are  supplied by the agents of the Lord, with the purpose that we  should make  proper use of them to keep ourselves fit and healthy for  the purpose of  self-realization, leading to the ultimate goal of life,  namely,  liberation from the material struggle for existence.
This aim of life is  attained by performance of yajnas. If we forget  the purpose of human  life and simply take supplies from the agents of  the Lord for sense  gratification and become more and more entangled in  material existence,  which is not the purpose of creation, certainly we  become thieves, and  therefore we are punished by the laws of material  nature.
A society of  thieves can never be happy, for they have no aim in  life. The gross  materialist thieves have no ultimate goal of life. They  are simply  directed to sense gratification; nor do they have knowledge  of how to  perform yajnas.
Lord Caitanya, however, inaugurated the easiest performance of yajna,  namely the sankirtana-yajna, which can be performed by anyone in the  world who accepts the principles of Krishna consciousness.
Hiranyakasipu planned to kill the inhabitants of earth so that yajna  would stop and the demigods, being disturbed, would die automatically  when Lord Vishnu, the yajnesvara, was killed. These were the demoniac  plans of Hiranyakasipu, who was expert in such activities.
SB 7.2.11 (Hiranyakasipu speaking)
The basic principle of brahminical culture is to satisfy Lord Vishnu,  the personification of sacrificial and ritualistic ceremonies. Lord  Vishnu  is the personified reservoir of all religious principles, and He  is the  shelter of all the demigods, the great pitas, and the people in   general. When the brahmanas are killed, no one will exist to encourage   the kshatriyas to perform yajnas, and thus the demigods, not being   appeased by yajna, will automatically die.
PURPORT by Srila Prabhupada:
Since Vishnu is the central point of brahminical culture,  Hiranyakasipu's plan was to kill Vishnu, for if Vishnu were killed,  naturally the brahminical culture would also be lost.
With brahminical culture lost, yajna would no longer be performed,  and for want of yajna the regular distribution of rainfall would cease  (yajnad bhavati parjanyah [Bg. 3.14]).  Thus there would be disturbances  all over the world, and naturally the  demigods would be defeated.
From this verse we get a clear indication of  how human society is  disturbed when the Vedic Aryan civilization is  killed and the Vedic  ritualistic ceremonies performed by the brahmanas  are stopped.
Kalau sudra-sambhavah:  because the population of the modern world  consists mostly of sudras,  the brahminical culture is now lost and is  extremely difficult to  reestablish in a proper way.
Therefore Lord Caitanya has recommended the chanting of the holy name  of the Lord, which will revive brahminical culture very easily.
harer nama harer nama
harer namaiva kevalam
kalau nasty eva nasty eva
nasty eva gatir anyatha
[CC Adi 17.21]
Because of the increment in demoniac population, people have lost  brahminical culture. Nor is there a kshatriya government. Instead, the  government is a democracy in which any sudra can be voted into taking up  the governmental reigns and capture the power to rule.
Because of the poisonous effects of Kali-yuga, the sastra (Bhag.  12.2.13) says, dasyu-prayeshu rajasu:  the government will adopt the  policies of dasyus, or plunderers. Thus  there will be no instructions  from the brahmanas, and even if there are  brahminical instructions,  there will be no kshatriya rulers who can follow them.
Aside from Satya-yuga, even formerly, in the days when demons were  flourishing, Hiranyakasipu planned to destroy the brahminical culture  and the kshatriya government and thus create chaos all over the world.
Although in Satya-yuga this plan was very difficult to execute, in  Kali-yuga, which is full of sudras and demons, the brahminical culture  is lost and can be revived only by the chanting of the maha-mantra.
Therefore the Krishna consciousness movement, or the Hare Krishna   movement, has been inaugurated to revive brahminical culture very   easily so that people may become happy and peaceful in this life and   prepare for elevation in the next.
In this regard, Srila Madhvacarya quotes this verse from the Brahmanda Purana:
vipra-yajnadi-mulam tu
harir ity asuram matam
harir eva hi sarvasya
mulam samyan mato nripa
"O King, the demons think that Hari, Lord Vishnu, exists because of  the brahmanas and yajna, but factually Hari is the cause of everything  including the brahmanas and yajna."
Therefore, through the popularizing of hari-kirtana, or the  sankirtana movement, the brahminical culture and kshatriya government  will automatically come back, and people will be extremely happy
SB 7.2.12
TRANSLATION (Hiranyakasipu speaking)
Immediately go wherever there is good protection for the cows and  brahmanas and wherever the Vedas are studied in terms of the varnasrama  principles. Set fire to those places and cut from the roots the trees  there, which are the source of life.
PURPORT by Srila Prabhupada
The  picture of a proper human civilization is indirectly described here.
In  a perfect human civilization there must be a class of men fully  trained  as perfect brahmanas. Similarly, there must be kshatriyas to  rule the  country very nicely according to the injunctions of the  sastras, and  there must be vaisyas who can protect the cows.
The word gavah  indicates that cows should be given protection.  Because the Vedic  civilization is lost, cows are not protected, but  instead  indiscriminately killed in slaughterhouses. Such are the acts  of demons.  Therefore this is a demoniac civilization.
The varnasrama-dharma mentioned here is essential for human  civilization. Unless there is a brahmana to guide, a kshatriya to rule  perfectly, and a perfect vaisya to produce food and protect the cows,  how will people live peacefully? It is impossible.
Another  point is that trees also should be given protection. During  its  lifetime, a tree should not be cut for industrial enterprises.
In Kali-yuga,  trees are indiscriminately and unnecessarily cut for  industry, in  particular for paper mills that manufacture a profuse  quantity of paper  for the publication of demoniac propaganda,  nonsensical literature, huge  quantities of newspapers and many other  paper products. This is a sign  of a demoniac civilization.
The cutting of trees is prohibited unless  necessary for the service  of Lord Vishnu. Yajnarthat karmano'nyatra loko'yam karma-bandhanah: [Bg.  3.9]) "work done as a sacrifice for Lord Vishnu  must be performed,  otherwise work binds one to this material world."
But if the paper mills stop producing paper, one may argue, how can  our  ISKCON literature be published? The answer is that the paper mills   should manufacture paper only for the publication of ISKCON literature   because ISKCON literature is published for the service of Lord Vishnu.
This literature clarifies our relationship with Lord Vishnu, and  therefore the publication of ISKCON literature is the performance of  yajna.
Yajnarthat karmano 'nyatra loko 'yam karma-bandhanah [Bg. 3.9]).  Yajna  must be performed, as indicated by the superior authorities. The   cutting of trees simply to manufacture paper for the publication of   unwanted literature is the greatest sinful act.
--
The demons  have tried various schemes which I shall now outlay so you get some  concept of the war which has happened so far.
Hiranyaksha and Hiranyakashipu  were two brothers. The plan of  Hiranyaksha was to adjust the position  of the Earth itself to cause it  to become influenced by negative energy in the lower regions of the  universe and completely change the inhabitants of the Earth. To this end  he was  successful in moving the Earth but lord Vishnu killed him and  put it  back where it belonged.
Hiranyakashipu reasoned that if he could  defeat the gods in battle  he could receive the worship of mankind. He  did heavy Tapasya and got  the benediction of Lord Brahma. With this  benediction the gods were  unable to defeat him and he openly ruled the  universe. He caused the  human population of earth worship him as God.  With this act he opened  the door for his own demise. He was eventually  killed by Vishnu.
The next great tyrant was Ravana and he got  benedictions from Shiva  and Brahma but he didn’t get worshiped as God.  He only defeated the  gods to become unquestioned ruler. He was a  Rakshasha and they are not  jealous of the gods worship. He just wanted  to make sure they didn’t  bother his indulgences. He offended the gods  and humans and Vishnu  incarnated and killed him.
It is described that  Indra killed many demons in a great war and  destroyed their planets and  kingdoms and so they were without a home.  Their subtle bodies however were  still intact so they came up with a  new plan. Take birth on the Earth in  human bodies.
With this new plan they hoped to evade the watchful eyes  of the  Devas and turn the world into their own kingdom subjugating the  human  race in a very subtle way. They did however plunder and rape the  earth  who complained about their presence to Brahma.
The gods were  summoned and decided to take birth on the earth and  fight them looking  like Humans. The history of the war was written down  as the great epic  Mahabharata, culminating in the battle of Kuruksetra  where the Bhagavad-Gita was spoken. Once again Vishnu came and aided  the gods in the  destruction of the demons.
That last great war happened over 5,100  years ago. No other great  war has happened since, that however doesn’t  mean it won't happen  again. It is said in the Vedas that the next incarnation of Vishnu will   happen in over 400,000 years at the end of the current age. But there   are records of many conflicts between gods and demons that happened   between the incarnations of the Lord.
What happened after the  Mahabharata is not known by the majority of  people but it has been  recorded by the Tattvavadis, the followers of  Madhvacharya.
The demons were angry at being defeated once  again and they realized  that they needed to be extremely subtle. The  problem had always been  that the gods would declare war on them as soon  as they made a move. So  they decided they wouldn’t make any open moves again  and they would  only use humans as pawns in executing their schemes. It would  essentially be the humans who did all the wrong and they would only make   suggestions and offers to man from now on, not taking any active role  in a  military sort of way.
They took birth around the world making bogus philosophies which  decried the performance of fire sacrifice and the  worship of the gods.  Men would no longer be content with the system as  it had been for  hundreds of thousands if not millions of years.
Instead  they would become discontent with life in all respects,  continually  searching and never finding, always asking but never coming  to any  conclusion.
They took birth as “holy” men and posed as "avatars" propounding  "spiritual" philosophies not based on any authoritative source and  spread  their false doctrines around the globe.
All of a sudden fire  sacrifice which had been a staple of all religions around the world  disappeared.
Hate, fear and death they preached and spread their foul  corruption of truth around the globe.
Millions were slaughtered in the name  of that which was holy. This  was their revenge upon the holy ones, for in  the name of truth, death  and hatred were spread which was the most  painful insult which could be  launched against the masters of goodness.
With this accomplished, men began to turn away from the very concept  of  that which was holy and began to eat the still more poison fruit of   godlessness which had been the plan of the demons all along.
Throughout history  however to make their plans come to pass the  demons have always had  agents. At first they incarnated to preach their  godless faith, however  afterwards they found many willing humans who  would serve them in  exchange for earthly powers.
So we have now come to the current situation of modern day secret  societies and can understand their real masters and master plan.
The Demons hope to turn this whole world into a godless materialistic  paradise.
They would be content if it was a desert with a few hundred  thousand greedy people.
They eat fear and pain like food.
Fortunately  for us, the gods decided to make a counter strike and  many teachers of  truth have come over the ages to counteract the  demonic influence.
But  there is always a constant fight because the demons will stop at  nothing to twist their words for their own ends.
This is the current  battle of light and dark. It has evolved from open interplanetary war  to the minds and hearts of mankind.
I do however get the feeling the  gods are not so ignorant about what  is going on and I feel if the demons  can't hold themselves back and  decided to try and destroy the world again, the gods  will make war with  them.
By covert means the demons have descended upon us and by covert means  did lord Krishna himself come as the hidden Avatar Lord Gauranga.
He came to establish the sacrifice for this age, the Yuga Dharma, Harinam Sankirtan.
The demons gain their power by the spread of hate and disunion, even  amongst devotees, and the only true means for all people to fight  against them is by joining together in Kirtan, free from all concepts of  cast and creed in order to glorify and serve the Lord.