Wow at the people in this thread that don't know how government works.
He has to ask Congress to pay for it because it is an American project. He isn't a dictator. Of course Mexico will provide fund and supplies.
But Mexico isn't going to just send a billion dollar check in the mail.
Let me not tho. Just like every past issue the left will outrage and overract only to be proven WRONG in the end.

Enjoy your brief weeks of undeserved self righteousness