Millions and millions of passengers are screened every year and so of course there are going to be lots of stories about airport security making mistakes. What you need to show is actual statistical evidence which I haven't seen any to date.
And of course it isn't just theatre. In 2011 over 1000 guns were confiscated by TSA and I am sure everyone can agree that guns do not belong on a plane.
You've left out vital context: how many guns were confiscated in 1999 or 2000, before the new security procedures? Also, of the guns confiscated at airports, how many were detected because we took our shoes off, gave up liquids, or had an electronic strip search performed?
