Tin Foil Hat time:
I believe that Trump was hoping the events of January 6 would give him the opportunity to invoke martial law and allow him to remain president "until the violence has ended". (which, given the unrest such a move would provoke might be a long time, possibly long enough for him to concoct some means of overturning the election.)
That's a conspiracy theory, founded on nothing more than circumstance. But consider:
-the removal of Secretary of Defense Mike Esper right after the election.
-Trump's unwillingness to deploy National Guard troops. The DC National Guard and Maryland National Guard were ready to deploy but weren't given approval to do so. Mike Pence and others were eventually able to work around Trump to give approval, but it took hours longer than it should have.
-lax security preparations, despite a lot of buzz on social media that something was going to happen.
-Trump alleged to have watched the events unfolding on TV with delight, and didn't issue his call for the rioters to disperse until it was clear that they had failed.
There were other things as well that give the impression that there was inside cooperation with the mob. Reps alleged to have given tours to Qanon types in days prior to Jan 6. Colorado rep Lauren Boebert live-tweeting Nancy Pelosi's location while the rioters were inside the Capitol. Rep Ayanna Pressley's staff reported that the panic buttons had been torn out of her office. Some Capitol police alleged to have removed barriers for rioters and even taken selfies with them. Trump's ally Michael Flynn urging Trump to implement martial law right after getting pardoned.
I mean, obviously none of this proves anything, but it does make me think that Trump was hoping this could be his own version of the Reichstagg Fire.
-k