Because their personal experience with MAGA in power somehow failed to match their expectations, and they feel betrayed.

Maybe they were just supremely in on the Epstein stuff and supposed allies backing down on their stance feels like a supreme corruption.

Maybe they were unemployed and didn't magically get a job. Maybe they were employed but thought MAGA would mean a raise but he got laid off for whatever reason. Maybe they went to a fast food place and the order taker had a Mexican accent despite assumptions they would all be out of the country.

Maybe they thought that the right wingers were right, but too passive and wanted to incite a hot civil war.

Or maybe he went all in on it and his wife left him and he blames people like Charlie Kirk instead of himself.

There's all sorts of ways it could be someone inclined to be MAGA. The conservative right played to a dangerous extremism and all sorts of things can go horribly wrong when you play with that sort of fire. Same goes for most any extremism.

In general, any extremist movement can appear all on the same page until they get real power, then all hell can break loose as they discover they don't perfectly agree on everything, or circumstances don't fully match their expectations.

Of course it could be a left wing person, or a foreign actor, or someone with a mental condition, we just have no inkling at all yet. It's just a possibility, and one that was represented in the two would-be Trump assassins.

I personally think it's more likely to be someone who agrees with his rhetoric rather than is opposed. He was very odious, but not really wielding real power, so I think someone inclined to disagree with him is less likely to be moved that hard to action compared to someone that might feel somehow betrayed by him. But lots of room for mental health to really be the driver and then all bets are off on any ideology.

The violent rhetoric they espouse is not limited to members of an opposing faction.