Why is Roman Catholicism attacked so much?

Archbishop Fulton Sheen once said: If I were not a Catholic and were looking for the True Church in the world today, I would look for the one Church which did not get along well with the world; in other words, I would look for the Church which the world hates. My reason for doing this would be that if Christ is in any one of the churches of the world today, he must still be hated as he was when he was on earth in the flesh. If you would find Christ today, then find the Church that does not get along with the world.

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Look for the Church that is hated by the world as Christ was hated by the world. Look for the Church which is accused of being behind the times as our Lord was accused of being ignorant and never having learned. Look for the Church which men sneer at as socially inferior as they sneered at our Lord because he came from Nazareth. Look for the Church which is accused of having a devil as our Lord was accused of being possessed by Beelzebub, the prince of devils. Look for the Church which, in seasons of bigotry, men say must be destroyed in the name of God as men crucified Christ and thought they had done a service to God.

Look for the Church which the world rejects because it claims it is infallible as Pilate rejected Christ because he called himself the Truth. Look for the Church which is rejected by the world as our Lord was rejected by men.

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Look for the Church which amid the confusion of conflicting opinions its members love as they love Christ and respect its voice as the very voice of its founder, and the suspicion will grow that if the Church is unpopular with the spirit of the world then it is unworldly, and if it is unworldly it is other-worldly. Since it is other-worldly it is infinitely loved and infinitely hated as was Christ himself. But only that which is divine can be infinitely hated and infinitely loved. Therefore the Church is divine. (slightly edited for readability)