You can always implement a surcharge on sending money out of the country. Imagine how the Saudis and Chinese would feel.
The trouble is that the federal government feels sorry for the POOR latinos and other persons feeling here. They don't feel sorry for us. So we keep paying for them.
Mexico has more millionaires per capita than any other country in the world. They are not poor, the country is top heavy. They refuse to help their poor and want us to bail them out.