If I put an AirTag in a suitcase and it doesn't make my connecting flight will find my tell me where it is?

More completely … if the AirTag’s intermittent beacon is “heard” by another nearby Apple device which is itself connected to the internet.

I’ve found that the tags in individually-handled bags are generally VERY findable as they make their way across the ramps and between terminals.

IF on the other hand, your bag is “buried deep” inside a wide-body cargo container for loading on a long-haul flight … maybe it’s not quite so findable.

Def gives you a nice “warm and fuzzy” when FindMy shows your tag in the vicinity of your connecting flight.

DO understand that AirTag beacons are intermittent … you will NOT be able to reliably watch your bag move thru the airport in “real time” as you might watch an iPhone.

I am just remembering an article where somebody said they were in New York from a flight from Paris and saw that their bag was in Japan or somewhere. So YES, but only if it can connect to say that's where it is. It's the same with finding a lost iPhone. If you're in a cave somewhere and drop your phone then it won't be able to connect to the Internet. That's what i was saying.

You were absolutely correct.

We routinely say our phones “connect to the internet” w/o listing the mountain of telecom hardware which makes that actually happen.

AirTags however, and IMO, require some “appreciation” of how they function as they are NOT “always on” …

… in a World where “always on” is too often assumed.

It should if the Airtag can connect to the Internet.