With aforesaid data in the background, I ask readers to enquire into and discuss if possible four questions: 1) Is it correct to say that religion is the main cause of war and killings?
The main cause? Not really. I think people will kill each other no matter what. Religion might be used as a vehicle or a pretext, just like politics or economics might also be used. Some people kill for some rather petty reasons, like some imaginary slight or even because someone might be snoring too loud.
In a world like that, a lot of people are afraid that other people might try to kill them. In the context of religion, people won't necessarily kill each other because of the religion, in and of itself. They might say "We're not killing them because they have a different religion. We're killing them because they're planning to kill us, so we want to kill them so they can't kill us."
In that sense, it's not the religion to blame as much as it's the fear and hatred which generates from it.
2) Is it correct to say that Islam is the main cause of conflicts in the world?
It sounds incorrect on its face, especially for conflicts which don't involve Islam at all. When it comes to conflicts in the Middle East, I'm not sure if it's religion that's the cause or if it's just ancient tribal feuds or maybe pan-Arab nationalism. My guess is that it's probably some variation of nationalism which appears to be the cause of conflicts in the world.
3) What worldview drives the materialistic motivation of maximising profit from war economies for the companies and countries?
Greed and a lust for power, I suppose. It doesn't seem to have any real "worldview" beyond "he who dies with the most toys wins." Just after WW2, the countries of the world got together and formed a United Nations and emphasized peace, human rights, and international cooperation. That was a positive worldview, and it was against that backdrop that nations and even companies conducted themselves.
Even when it came to war, our position was that we didn't like war, we didn't want to start any wars, and we had no designs on any extraterritorial expansion or annexation. Supposedly, we weren't out for plunder or booty, and we respected the independence and sovereignty of other nations. Our only purpose was to protect other nations or bring freedom to other people fighting against tyranny. At least, that's what a lot of politicians and many patriotic Americans have told us over the years.
As for the manufacturers, the people who make the weapons and munitions to carry out all this killing, they might say they're just fulfilling a need created by others and that "if they didn't do it, someone else would." Casino operators, drug dealers, and porn merchants probably use the same argument. They might make money from it, but they don't see themselves as the cause or creating the need in question.
4) What peaceful loving individuals can do to mitigate the demonic power of private merchants of death?
Well, all the workers of the world could unite, overthrow their capitalist oppressors, and form a worldwide workers government and implement a socialist society of peace and love all around the world.
That would be my suggestion. Oh wait, you said "peaceful." There may not be any peaceful way of doing it.
and 5) What scientists can do to minimise damages from potential misuse of scientific and technological advances?...
I think it ultimately comes down to whoever holds the political power. Whoever built the machine is not so much an issue as to who controls the levers and switches. Scientists, as well as the weapons manufacturers, are citizens within whatever political jurisdiction they're living, and they're subject to the laws and edicts from whatever government they're subject to.
If we don't want factories that build weapons, we need only pass a law against them. If we don't want misuse of scientific and technological advances, then we can pass a law against that - and hope that the people obey such a law.
But whoever holds the political power holds the key. And for that reason, there are a lot of people competing with each other and vying for political power - and all too often, people are disinclined to play nice. Politics is a dirty business, and it is said that "war is the continuation of politics by other means."
I don't think we'll ever be able to do away with war, but perhaps there might be certain methods of war which can minimize civilian casualties and collateral damage. If there's a dispute between two governments, maybe they can have some sort "trial by combat" between two champions. Leave the innocents and the rest of the population out of it. I saw a movie where countries would have their champions inside these giant robots where they'd fight it out.
Also, war is not just a matter between countries, but it seems that in the future, wars won't happen much between established nations and governments as much as it will be a matter of governments at war with their own people. Sometimes it's class based, or sometimes it might be based in ethnic tensions or religious. Some governments are so incompetent or corrupt that the people revolt, and then they need to buy weapons to quell the disturbance. But some other weapons dealer might sell to the rebels, thinking that if they win, then they would have a friendly government in their debt. It depends on what resources are available in a country - or it might be in a strategic position.