Just wondering if that’s standard in US airports?
I don’t know about JFK but I was at Reagan National in Washington on one of the 9/11 anniversaries and it was being guarded by a collection of military and members of multiple sheriff and police department as well as state police troopers.
Sometimes yes, sometimes no.
It’s a bit worrisome to see.
I’d say generally no, although maybe JFK is somehow different.
I mean, I haven’t seen military people (other than fellow travelers) in an airport in something like 14-15 years. For a short period post-9/11, there were National Guard troops in a lot of airports, but that hasn’t been the case for a very long time now.
I don’t recall ever seeing them here in the US, but I did in Paris in the mud-90s, well pre-9/11, of course. Train stations, too.
This has been repeated a few times since 9/11, at least in certain cities. There were definitely some soldiers in JFK after the Brussels attacks this spring, for example.
Lately, yes. Also in Penn Station.
Possibly still on alert from the Chelsea bombing:
I’ve seen them in 2 out of the last 5 times I’ve flown out of Boston. It’s not the norm, but it’s more common these days especially during times of heightened threat ratings. But it looks like it also happens at random times, not sure what the rational is for that. But if anyplace in the US would have more heightened alerts that would by the transport hubs in NYC and Washington.
Yes. I see them in Grand Central too, sometimes. I think they’re National Guard.
Are you sure they’re military?
The NY Port Authority police and the customs / ICE guys have teams that wear pretty much military style clothing and carry pretty much military style weapons. TSA has SWAT teams that dress that way too.
If you saw military rank and US ARMY embroidered over a pocket it’s military for sure. If not, it’s probably not.
Which is not to say that military are never seen doing guard duty at airports. But that at JFK at least the odds of a random guy with a big gun seen on a random day being military is rather low.
They’re almost certainly NY National Guard. Every time there’s an incident, they start showing up at train stations and airports for a few weeks after. I believe quimper’s theory about the Chelsea bombing is correct.
If TSA/DHS is thinking about it in the same vein as military base security, the rational is to be intentionally random. 
Randomness makes any threat have to plan for the risks of more stringent controls than they’d see most days. That let’s the security force avoid the costs (and hassles to those going through security) of maintaining all the more stringent controls on a day to day basis. It also keeps from sending a clear signal about how much information the security force has on the threat. (“Is today’s change in response to something they know about what we’re planning or just another random change?”)
TSA definitely has a policy of deliberate randomness in many things. Despite all the jokes. As you say, it’s a sound economy of force measure.
Yes everytime I have been to JFK they have been there.
As well as Penn and Grand central.
I remember seeing them in Amsterdam’s airport back then as well.
Here in the UK armed police are very rare. I pass through Stansted airport about 50 times a year and there’s almost always a couple of police walking around with big guns. I’ve seen the same thing at other UK airports, but not with the same regularity. Stansted is the UKs dedicated hijack and terrorist airport* though so that may be why.
Stansted is the airport they will try and redirect any hijacked planes to as there are special areas set up to deal with it. They have a line of trees set up to give cover to snipers and assault teams!
I’m in JFK right now. Seeing the usual assortment of over-armed police. No military.
Not to say they weren’t here when the OP came through.
JFK is a big place. Maybe it depends on the airline and/or destination? Pre-9/11 I flew from Frankfurt to Tel Aviv on Lufthansa. Pretty normal police presence around most of the airport, but getting into the boarding area for the Tel Aviv flight was like entering a fortress. Multiple security checkpoints with 6-10 heavily armed guards at each one, plus more in the holding area. Not sure if the guys with the automatic weapons were police or military, but from the way they marched from point to point in formation makes me think military…