Since he is not answering the first question, let me try and answer.
At least in 2012.
http://us-foreign-aid.insidegov.com/q/112/1590/How-much-money-does-the-U-S-give-to-Mexico
Read that.
If the US withholds financial aid, to contribute to the building of the wall....
You think nat will see where I am going?
We're looking up different sources, aren't we.....
How much foreign aid does the United States give to Mexico?
In 2013, the United States gave Mexico $51.5 million in foreign aid. Of that amount, $24.8 million, the largest segment, was designated for democracy, human rights and governance. The next largest amount, $10.9 million, was designated for the environment, and $8.4 million was designated for economic development.
How much foreign aid does the United States give to Mexico?
Bear in mind that if we withheld the $51.5 million from Mexico, that would probably pay for the hinges on the gates of that wall.
You realize that's every year, not once, right? Or do you? I think we should pay for our own security, but that wasn't your question. Clearly he could force them to "pay" for it one way or another. Mexico is too dependent on us