This was the problem with George W. Bush’s speech attacking the president and Trumpism. Bush unquestionably has the standing to criticize Trump’s character and conduct. Substantively, though, the speech had a strong whiff of nostalgia and betrayed no self-awareness of how Bush’s failures, real and perceived, contributed to the rise of Trump.
Bush isn’t even really taking account of the sources of his own support. He denounces nationalism, yet the wars in Afghanistan and Iraq had significant nationalist backing at the outset and, when they lost it over time, became unpopular and unsustainable.
Trumpism won’t reign forever. Whatever comes next in the party is likely to borrow from his populism and nationalism, and certainly won’t snap all the way back to Bushism.