TL;DR - Trump fulfills campaign promise, stock market rallies, liberals upset.
Wasn't his campaign promise that Mexico would pay for the wall?
No. Not at all. This is an example of taking the rhetoric of a negotiator too literally. It's like fact checking the statement hamburgers "a mile high" and claiming it to be a lie.
The point is that immigration needs to be controlled by a country.
Secondly, there's over 1,000,000 legal immigrants per year so I don't want to hear that cutting illegal immigration is xenophobia.