Transportation Security Officers, are officers because that is the title and designation provided by OPM. This fact does not make them "law enforcement officers" just as the fact that a title does not include the word, "officer" does not mean that the individual is not a "law enforcement officer" (Special Agent being the most common designation for a federal law enforcement officer).
Hopefully this tired old debate can end as it's just plain wrong. Yes, they are "officers" and yes, they are not "law enforcement officers."
Next.