I think I’d tell him, I’m declaring this an emergency, and I’m ordering funds allocated for the wall, and our military to start building it.
I don’t think he’ll go into detail about the “what ifs” he can simply say that he would still like to see funding for the wall thru Congress. He wants a bill from congress that addresses the immigration issues, and he’ll sign it.
I don’t see why he should keep the gov’t shut down, if he’s going forward with the national emergency, do you?
Well, this is the order in which I see things happen under your scenario:
Trump declares emergency, starts ball rolling for military to fund wall.
Trump signs a Continuing Resolution to reopen government, but the CR has no wall funding in it.
Government reopens.
Dems then sue and the wall is put on hold by a judge issuing a restraining order until the case can be litigated, but in the meantime government is still open.
Six months later the Supreme Court either lets the lower court injunction stand, or rules against Trump re. emergency declaration.
We get no wall, and the Democrats get credit for re-opening government.
No, I don't think that declaring an emergency is the correct path for Trump. He needs to stand firm on the shutdown until the Dems give him his wall funding.