I get the feeling this was both a trap to use an excuse to cut aid off to Ukraine by goading Zelenskyy but also to try to force regime change in Ukraine, for example, they will want to paint Zelenskyy as the unreasonable party, they goaded him into a conflict and they will now blame him for messing things up and losing American support, they will try to turn Ukrainian politicians against him, say he is not fit to lead and has to step down if Ukraine wants America's continued support, they want someone unlike Zelenskyy, would cave to their demands and surrender to Russia.
I do believe this pathetic display will only increase Zelenskyy's approval rating in Ukraine though and make Ukraine even more patriotic.