That was their judgment. It no longer matters whether they were right or wrong. My initial posts here showed empathy toward both her and her husband for being upset.
What is not OK, is shouting and throwing your arms around, throwing a temper tantrum in an airport. What is not helpful to your upset wife is getting yourself arrested with a big display of bravado. What is not reasonable is to blame this incident for his wife getting a c-section, and what is not acceptable to me is turning this into a broad condemnation of all the people trying to find weapons on people getting on planes.
There are self-appointed freedom fighters here who would argue against any law enforcement officer anywhere who ever inconvenience anyone in the thousands of judgment calls they have to make every day. Nothing will ever be perfect, bad guys can foil any system, but I would rather have them there than not, and their job is not easy.