About he accusation and 45/140's mind state in the moment
This is speculation.
Forget for now the theories and tweets since then. In that moment when he was pressing off his tweet he never for a MOMENT considered the import of what he was saying. He needs a foil. Obama was a successful one for him. He had said he was born in the USA so he needed a new tack.
AHA!
WIRETAPPING.
He'd heard about it on all his go-to news sources, all of which inhabit FantasyLand. He reads some bullshit Breitbart story and AWAY HE GOES.
No thought for the weight of the charge. It was a GAME to him. A throwaway. Spaghetti thrown against a wall to see if it would stick.
Just another morning tweet when his minders were sleeping.
But now it has EXPLODED. And he has no clue how to fix it. He now realizes this is the big league. Not him "billion" dollar family business where he has to answer to no one.
Now he is in No Way Out mode and he's a hurting old man. He is almost universally reviled. And ridiculed. And disrespected. And nearly irrelevant. All by his own hand.
Meh. I wish him a life of painful emotional misery.