It's pretty much given now that Nixon and Kissinger participated in a plot with then-South Vietnamese President Thieu. The Nixon plan was to stall Lyndon Johnson's 1968 peace talks to get a better deal when Nixon would win.
And while we haven't declared war on anybody since World War II, at least Congress (Gulf of Tonkin) declared North Vietnam an enemy of America.
Clearly Nixon, Kissinger and others were guilty of "treachery."
As in treason.
Unfortunately, we will have to wait until at least 2021 for any criminal investigation to begin.
You hang in there Henry.