https://www.bostonfed.org/-/media/Documents/Workingpapers/PDF/wp1407.pdf
I heard a report this morning on NPR about the high percentage of US health care workers who are foreign-born. For instance, one-quarter of US medical doctors are foreign-born. 14 percent of US RNs are foreign-born. However, the percentage is much higher in California, New York City and South Florida. Over 50% of RNs in LA, NYC and Miami are foreign born, and the numbers are higher for nursing aides.
Nationwide, a high percentage of RNs are immigrants from the Phillippines.
The linked research paper presents economic arguments that the influx of foreign-born nurses has caused less action to be taken to improve the working conditions of all RNs, and delayed actions to increase the numbers of seats in nursing programs. A large number of nurses quit the profession each year, and the theory is that fewer would quit if working conditions would be improved. There is less need for the health systems to work to retain nurses because they can fill their spots with foreign-born RNs.