Go after Trump? That's what political debates are about! They go after each other!
It's clear Trump is scared as hell to go man-against-man with Cruz in a policy debate. It would be no contest - Cruz would wipe the floor with Trump.
Trump is very smart to retreat to his safe space where he can tell his followers how great he is without having to step into the ring with a world class intellect like Cruz.
Cruz gets a pass at answering questions during debate. Cuba and torture to name a few. He has skated this entire primary. Anyone else who had won 3 primaries and a handful of caucus’ would have been laughed out of the campaign by now. Don’t get me started on Kasick. Both of these guys have not been vetted at all.