Blah blah blah...4th amendment blah blah blah.
Screening of your bags is NOT a violation of yours or anyones 4th amendment rights, as acknowledged by the Supreme Court. If you actually believed that, then challenge it. I know I would challenge any violation of my rights. Why don't you do it?
As for something being put INTO a bag, any reports of that? No? Then that must be a non-issue too.
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"All life is a concatenation of ephemeralities" - Alfred Kahn, American economist