After all, a $400 billion dollar remittance market is not exactly pocket change.
More to the point of our national interests, though, should be the consideration of what kind of foreign aid demands (both practical and humanitarian) we would be facing if that need were suddenly exacerbated by the lack of hundreds of billions of dollars going to it now. The hundreds of billions that had to first be created by someone working steadily at a job in the country they immigrated to.
So, in addition to the real, direct, economic benefit (paying sales taxes, employment taxes, and income taxes, in addition to the value added to the business itself. And let's also remember that they are most likely to also be doing the really low paying work we won't do, or the highly technical jobs that there aren't enough of us trained here to do--because education is also a commodity, and costs too much... Don't get me started on that one), these people do three times as much in foreign aid than the rest of the world combined. Three times as much need that we might be facing in people becoming desperate, that we do not have to contend with because these folks overcame great risk, and abundant difficulties, to work hard where they ended up, so they could help their loved ones back home.
Wow. Doesn't that just provide bedrock foundation for the suspicion that they are nothing but a crime prone, terrorist infested, scourge. Something I'm sure our de facto ex president will soon come to flip to "Who knew the immigration thing was so complicated? I mean. I saw a number today in a tweet. $400 billion. Who knew?"
The other thing, though, that more light on the subject will provide, is making sure these people get a fair deal with the service of having money transferred; an area of commerce in the past that has been subject to a lot of profiteering in the past. The article linked below gives some hope for that, but, as has already been posted, real competition in Capitalism has become a quite chaotic thing in itself. And so this is something else we'll have to keep an eye on.
The Fight For the $400 Billion Business Of Immigrants Sending Money Home