How can American companies make the workplace environment safe and efficient without treating employees like suspected criminals?
It depends on what type of companies and what type of jobs you are considering. I don't know why making an environment "safe and efficient" would lead to employees believing that they were "suspected criminals."
With terrorist activities, various searches and restrictions might be needed to try to avoid destruction.
Efficiency is improved when employees know their duties and responsibilities and the rights and privileges that go along with them. However, I don't see how that would lead them to feel suspected of anything.
Do you think you could be more detailed in your question? What type of companies? What workplace environments? Are you talking about factory work? White collar work? Skilled or unskilled employees?
I'd like to give a better answer, but I can't do so unless the question is more specifically defined. I hope this helps a little. Thanks for asking.