Let me remind you that the government of the United States is still "of the People, by the People, and for the People." Mark Felt's duty to the People of the United States overwhelms any so-called loyalty to a criminal scumbag like Nixon. Mr. Nixon sought to deceive the People and subvert the political process. No government official owes any loyalty to a leader such as that.
Nixon's own taping devices caught him and his cabal plotting the cover-up among other dirty tricks and utterly racist speculation. They also reveal that he controlled Felt's superior, L. Patrick Gray, so STFU on crap about how he could have worked within the FBI:
During the confirmation hearing Gray defended his agency's investigation,
however, during questioning he let it be known that he had handed over the files
on the investigation to White House Counsel John Dean, in spite of the fact that people with strong links to the White House were being investigated. [Answers.com]
Watergate was not some illicit extramarital affair, fools. It was a serious crime that threatened to subvert the American political process, and it involved burglary, wiretapping, breaking and entering, and bribery. Not to mention Nixon used his position to appoint toadies like L. Patrick Gray to authoritative positions so they could squelch or corral any problems. Ever hear of the Saturday Night Massacre? Serious, serious abuse of power.
Get real, freaks, and try to keep straight who it was that ordered the break-in and subsequent cover-up in Watergate.