Nixon in fact was corrupt. The charges against him did have some merit. Nixon had to make a great speech to cover up his own corruption.
The charges against Palin have no foundation. Palin's speech wasn't trying to cover up or compensate for anything.
Knowing what is known now, would it be a moral act to go back in time to Munich in 1927 and assassinate Hitler? The point is, Nixon attempted to thwart the global Communist/Socialist conspiracy. For the greater good of America the ends might justify the means.