Nixon wasn't in office yet, but he did have his campaign manager got to Vietnam and promise the VietCong a better deal if they walked away from negotiations, which lead to FIVE more years of war and countless lives lost for nothing other than a point to talk about on his soap box

The difference seems to be that Nixon may have been crooked, but he was largely competent. He operated on experience, expertise, and causal reality. Our current political situation is largely free of facts, knowledge, or causality. Much of the corruption that happens today is in plain sight and basically ignored. The goal is governance through depoliticization and post-truth infotainment.

Note that Nixon was actually impeached by his own party and would have been removed for what would now be a single day of news cycle, only on a few networks/papers, and completely ignored by a major political party.