Is there a lick of unity within the Protestant Churches?

I mean they all seem to gang up against Catholics for some reason. Is that the ONLY thing they share in common? A Baptist is not a Lutheran, A Presbyterian is not an Episcopalian. A Church of God member is not a Bretheran. A Holiness is not a Quaker. They have so little in common...no common creed, no common leader or form of worship. Is there ANY unity among Protestants? If so, what is it? And how different is THAT with Catholics, since Protestants were ALL CATHOLIC for 1500 years after Christ! They ALL claim to be "right" and yet nothing in common. Then they say Catholics are not Christians. How does that make a lick of sense?