It probably has a lot to do with the way Trump treated Jeb.
I think it runs deeper than that. Trump has been openly critical of the Iraq war, and at one point said that Bush lied about WMD. He walked that back, but he wouldn't have said it in the first place if he didn't believe it.
GWB can zing everybody he pleases with the frat boy-style nicknames he makes up, but don’t anyone dare call Jeb “low energy” or some other snarky thing.
You mean had a lot to do with how Trump trounced low energy Jeb. Jeb is an embarrassment, I'm wondering how he ever got elected statewide.
*Jebra*