I'm perfectly calm, although I do find it upsetting when people blindly put their faith and trust into institutions of which they know little or nothing.
You asked how their search was illegitimate. Just because they are "allowed" to do something (per their own statues via DHS) does not make it Constitutionally lawful nor morally right. Thus, illegitimate.
Their qualifications, procedures, and justifications are no different from letting a crack head fondle your kids on their way to school, because they say they do it for the children.
None the less, they are permitted to search and I can say with reasonable confidence they don't search just to mess up someone's Axe FX. International Law doesn't follow the Constitution of the United States of America. I don't find your analogy justifiable, either. Let's agree to disagree.