I am afraid we are living in a Police State - in the broadest sense of the term. Our freedom has been almost terminally eroded for "safety" and "security" reasons. We just cannot argue, and expect to win, with anyone stopping us doing something on alleged "safety" or "security" grounds. You are likely to get locked up! We have a frightening culture at the moment.
You can't blame the people on the front line. Yes, maybe the security guys are unpleasant at times. Maybe they are underpaid and maybe they are totally hacked off by the pathetic passengers and their whingeing.
So we have a dicotomy.
The logical thing to do is express our serious concern about the present "Police State" culture in Britain (and other European countries, incidentally), to those in power. To MPs, to Police Chiefs, to Security Chiefs, Airline Chiefs, Airport Chiefs, etc. This takes a bit of effort but it can be done at home.
What we shouldn't be doing is giving the guys on the front line a hard time, as this will just make things worse for us all.
And may I suggest that any letters that are written to "important people" should be well written, polite and persuasive, with examples of issues being complained about. They will then get treated with respect.