The security risks are far beyond ordinary protocols, knowing from what was learned Sept 11th. The superlative dedication of 18 or 19 suicidal fanatics to have agreed to die on the same day supersedes ordinary comprehension.
Persons as such could have C4 plastic type explosives wrapped around their bodies and penetrate airport security checkpoints and become human passenger bombs aboard airliners. Pan Am 103 demonstrated that only a small explosive pack is required to rip open the fuselage, cause decompression and eventual structural failure.
For true checkpoint security, passengers must be padded down until plastc explosives detectors are installed. Suicidal fanatics cannot otherwise be stopped.