If they jail him, this could be one of those political events that sets off a cascade of unknowns.
Yes, he is. I think he means it but I think Trump is pushing Merchan until he snaps but Merchan is the one really bluffing. No way Merchan puts Trump in jail, it would be a logistical nightmare for the city/state. Merchan will continue fining Trump and will lose credibility, a la the Boy Who Cried Wolf, every time he does.