Guantánamo Bay, 15 years on. A holding pen in the Caribbean for people you don't know what to do with — what does that bring to mind? Oh right: Guantánamo Bay.Just to remind you: Guantánamo Bay is a U.S. naval base, 45 square miles, on the southeastern tip of the island of Cuba. We lease it from the Cuban government. It includes a detention camp for irregular soldiers — that is, armed fighters not members of any nation's military — captured during our military expeditions in Afghanistan, Iraq, and some other places.These fighters presented us with a problem right away. The model we were using was the prisoner-of-war model; but that assumes your prisoners belong to the regular military of some nation you're at war with. When the war's over, bureaucrats from the two nations get together and work out repatriation arrangements.That couldn't work for these irregulars. It sometimes isn't even clear what nationality the prisoner is. The most famous current inmate at Guantánamo Bay, Khalid Sheikh Mohammed, was captured in Pakistan and believed to be a Pakistani citizen. He wasn't in the Pakistan military, though; and he may actually be a citizen of Bosnia.If he was captured in Pakistan, why didn't we let the Pakistanis deal with him? Well, because (a) the Pakistani military and political establishments are filthy with jihadist sympathizers and corrupt as all get out, and (b) he had information we wanted to get out of him. So off to Guantánamo Bay he went. Fourteen years later, he's still there.When Barack Obama became President in 2009 he promised to empty out the detention camp and close it. His idea was to bring the prisoners to the U.S.A. and try them under U.S. law. Guantánamo Bay is not U.S. territory, so they can't be tried there. Congress didn't like the plan, though; so the prisoners we couldn't release — currently about sixty — are just stuck in limbo there.It's an awkward situation, and no-one seems to have a solution for it. It doesn't look as though Donald Trump will allow any more releases. Tuesday this week he said — I mean, of course, he tweeted — tweet: "There should be no further releases from Gitmo. These are extremely dangerous people and should not be allowed back onto the battlefield." End tweet.That's actually a back-off from his campaign rhetoric. Back in February he not only promised to keep the prison in business, he also said, quote, "we're gonna load it up with some bad dudes, believe me, we're gonna load it up."You don't have to be a bleeding heart to be bothered about this. I personally wouldn't lose any sleep if the Guantánamo Bay prisoners were taken out and shot in batches, if someone could prove it was constitutional to do so. Nobody seems to think it is, though. Legal eagles seem to think the prisoners are entitled to some due process; but without bringing them to the mainland, which Congress won't allow, it's hard to see how.The trend in policy here seems to have been simply to stop taking prisoners in counter-terrorist operations. Just zap 'em with drones. That works for me too, but it can't always be done.Say you're leading a Special Forces boots-on-the-ground operation, and Mohammed bin Mohammed comes out with his hands up and begs to surrender. According to the Geneva Convention, Article 41 of the 1977 protocol, he is then hors de combat and, quote, " shall not be made the object of attack," end quote.Sure, I know: rules of war, hollow laugh, ha ha ha. But when you think how over-lawyered Western society has become, and recall the things that have happened to guys who ignored the rules — like Sergeant Blackman of Britain's Royal Marines, currently serving a life sentence for offing an Afghan prisoner in a combat zone — you have to think a prudent soldier would take Mohammed prisoner and leave his future disposition to the suits.And what if the guy in your drone sights has some really vital information you'd like to get?There aren't any good watertight solutions here. It would surely help, though, if we secured our borders and points of entry properly, stopped admitting Muslims for any purposes other than diplomatic, and withdrew visas from noncitizen Muslim residents, obliging them to go home. That would at least restrict the terrorism problem to our own citizen nutcases, who we could deal with constitutionally; and there'd no longer be any strong reason for our troops to be chasing jihadis around the Hindu Kush.