So why is a church and its political aspirations left holding the reins here?  

Protestant pilgrims barely got a foothold on this continent largely because the native population had been wiped out by plague---They almost starved to death amid cultivated fields, and would have, but for the efforts of natives who were rewarded for their kindness with genocide.

Sure, puritans played a role in the colonization of America, one celebrated in our national mythology, but they had little or nothing to do with founding our country, which was and remains a melting pot of many religions and no religion, many cultures and many visions--Its strength, and its future, lies in incorporating them all.