I’m sure the Danish PM told him when he called her about Greenland.

Trump is talking to the Americans. He has no diplomatic skills. He would reply “so are you” and the whole scene would broadcast on Fox and watchers would cheer. It would serve no purpose.

nothing, maybe some trade shit? It would make the leader in question look worse for stooping to his level

I sorta wish zelinsky did in that rediculous display a bit ago. Lets face it, its not like trumps gonna be doing him any favors.

EU told Ukraine to go sign this deal to not upset America…

Ukraine got ambushed for a teevee show episode.

Will EU step up now or will they continue thinking US it is still US’s job?

They’d instantly gain the respect of roughly half of all Americans and probably most of the western world.

It entirely depends on the nation in question. Putin could do it and slap Trump and it would be ok