I’ll have to agree with Greenwald, with the caveat that it didn’t start with Nixon. There has long been something as ridiculous as “diplomatic immunity” in place, and prior to Nixon, presidents were better shielded from their crimes – perhaps Nixon was unique in that he was such a mental case that he didn’t allow himself to be better shielded. At any rate, elite immunity has also always been a part of our legal system, it just hasn’t been so well used in politics until Bush II. Other presidents could be accused and justly charged with war crimes, they just weren’t accompanied by systematic torture and they were generally more limited in geographical scope at least. Mark Twain railed about the issue quite often, and since then, the Spanish American War, both world wars and frankly, every war since has come with political aspirations and designs on Empire that included faked or manipulated acts by “the enemy.” Acts of military aggression are war crimes. When was the last time a foreign army invaded and we put our military to use to defend ourselves? Nevertheless, we have kept it busy.
At any rate, the Greenwald quote is from his new book, should you wish to investigate further: With Liberty and Justice for Some. You can just read the cited article if you’d like to have the exact - disgusting - words that Gerald Ford used to “justify” his pardon of Nixon. Words which were praised by Dick Cheney, of course, and parroted by many, including President #Compromise, since then in defense of the continued policy of “looking forward.”
....but hey, do what you want....you will anyway.