That is funny.
Actually, Trump has a physical wall. It's himself. No one wants to come to Trump's America.
Having said that, Americans may need to offer support to Trump as things are getting rather serious re Russia and Syria.
Virtue-signalling here. But while I was against Dubya's war, once he was engaged, I quit arguing that he was wrong. After the decision, what matters is the lives of the combatants and supporting them (ie our side) during a war is non-optional for me.