Because there aren't enough "equally qualified nurses".

> There is a lot of under-employment for highly qualified US citizens.

No, there isn't. Even with the current AI mess, the unemployment for highly-qualified software engineers is 2.8%: https://www.ciodive.com/news/june-jobs-report-comptia-data-I...

The AI is now decimating the jobs for the recent CS graduates.

under-employment != unemployment. I carefully selected my words. And you switched from nurses to highly-qualified engineers.

qualified nurses are having to get jobs at retail, etc to survive. For some sectors, it's importing cheap labor (aka wage suppression).

Hmmm, so a nurse can come from any country with any level of English and work in a US hospital without re-certification? There is a smell to this claim…

The same applies to nurses. The nurse shortage has been basically non-stop since 80-s: https://nursejournal.org/articles/the-us-nursing-shortage-st...

Long term shortages are evidence of supply controls or price controls. If nurse compensation was allowed to rise to its natural level the shortages would solve themselves. High compensation pulls people into a profession. Suppressing compensation with imported labor cures a short term problem but creates a bigger long term problem.

In this case, it's the evidence of the failing education system or misplaced incentives.

You also are missing another possibility, the nurse jobs can just disappear and patients will be left with worse care.