They should know by now that Trump is a counter puncher. He’s told them that for four years.
But, crazy unca’Joe just doesn’t understand.
But, then, he’s senile, so...
They simply don't have a strategy for dealing with that, other than complaining, saying "oh, how terrible" and a few variations of varying intensity.
Their intellectual "braintrust," if you want to call it that, has no ideas, nothing in the till. The cupboard is bare. The last thirty years of feckless Republicans have so thoroughly conditioned them to expect the cringing apology, the embarrassed retreat, the series of concessions offered in a futile attempt to buy forgiveness... anyone who might know how to deal with something else has been purged from their party and their philosophical backers and supporters.
Trump is forcing them to think outside the box... and there is nothing outside the box but empty space.