The same reason that a congregation of Muslims can shut down one of the busiest sections of New York city in order to pray publicly, and hardly anything is said. But, one christian can kneel on a football field to give glory to God and the whole country comes unglued on him.
Satan is the Prince of the Power of the Air in this world. This is his kingdom. He rules it. Christ said, "My kingdom is not of this world." Christians are at a disadvantage in this world. Whether Muslim, Hindu, Buddist, atheist, or any other religion, the large majority of the world are anti-christ.
Jesus said, "I am the way, the truth, and the life. No man cometh to the Father but by me." And, he is. And all those who reject him, reject God. That is why christians come under attack from all sides when we speak out for God. Satan is a liar and he only attacks the truth. So, his followers are the same.