The real problem, in terms of peace on earth, is connected to Atheism and the nonreligious, who makes their own relative laws. That is the easiest path and is based on relative morality of the ego.
Christianity may be the most difficult, in the sense that love your enemy and turn the other cheek, requires one be accepting of all other religions and non-religions. It is really the people; fellow humans, who really matter not how they dress up in terms of dogma. Many religions can just clan together, and only have to be concerned with their clan group.
If you only have to protect and reinforce the clan, there is mutual positive feedback from the clan, since you are a closed symbiotic system. But if you have to accept all, and even turn the other cheek, you often have to deal with taunting negativity and hostility. Atheists often tell you that you are a hypocrite if you do not turn the other cheek, as they work to undermine you.
The Atheists are much less offensive tø religions, with an eye for an eye philosophy, who will use the system other means to fight back. There are terms like anti semitism or Islamophobe, designed to shut down discussion, before the feud can get out of hand. There are no terms like anti-Christian or Christophobe, that work the same way. There is more pressure on Christians, who have to learn not to let their ego be delicate. This is why they are strong and many become secular leaders based on fairness to all.
The Supreme Court in the US is mostly Catholics, since these people are not only smart due to their hard work and commitment, but assumed to be objective and fair to all, since this is how they are taught to walk life. There are no Atheist on the Court, since they are more self serving and not very open to strangers outside their own clan. The religious people are more than half the population, yet these people would be denied and victimized by any Atheist Justices. Atheism is the easiest religion to follow since there are no requirements besides hate religion and God. All else goes. This is what prevents peace on earth.