Companies do not want to commit to long term employees. So the trend in the past 30 years has to increase the share of consultants from 5% to 50% in most big shops. Many Citizens don’t want to work as a consultant. They want security. Other citizens are picky about the technology they will work with. They don’t want any job that would have them. Other citizens are picky about the company they will work for. Not everyone can work in Silicon Valley. Maybe their best job is in a less prestigous place.Total BS. At the right price you can fill every job in the USA with US citizen. It is called supply and demand you should study that theory. It may help you.