[PeterPrinciple]

I am willing to be corrected but my logic says these are US Dollars that eventually will have to be spent here in the US. The only question is when they will be spent.

[1stFreedom]

It may be US dollars, but remember, the is NO federal sales tax (outside of Gas) on consumer goods.

So, they aren't paying a share of the Federal Burden -- but may be recipients of such tax dollars (roads, etc).

[FITZ]

There is nothing saying those dollars must be spent in the US --- they can work their way through the Mexican economy --- bus drivers, electric companies, store owners ---- on up to the wealthy who can vacation in Spain or import goods from China.