President Donald Trump has threatened NATO ally Turkey if it crosses a line in the northeast of Syria, where the US is pulling back troops and allowing a Turkish incursion.

The US-Turkey relationship has soured over the past several years, but the US still stores as many as 50 B61 gravity bombs at Incirlik Air Base in Adana, Turkey. However, The New York Times reports, some US officials are quietly discussing plans to pull the weapons from Incirlik.

On Monday, The New York Times reported that US officials were considering plans to move the US nuclear arsenal from Incirlik air base in Turkey.

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On Monday, The New York Times reported that US officials were considering plans to move the US nuclear arsenal from Incirlik air base in Turkey. This move would be likely to further deteriorate the tense relationship between the US and Turkey, which has rapidly devolved as Turkey invaded northeastern Syria in assault on the Kurdish forces that fought ISIS alongside the US.

Following an announcement Oct. 6 that the US would pull troops out of northeastern Syria and would not prevent an incursion into the area by Turkish forces — effectively abandoning Kurdish Syrian Defense Forces instrumental in defeating the Islamic State in Syria — Trump issued a warning to the US's NATO ally.

"If Turkey does anything that I, in my great and unmatched wisdom, consider to be off limits, I will totally destroy and obliterate the Economy of Turkey (I've done before!)," he tweeted the morning of Oct. 7.

While the US's relationship with Turkey has been strained due in part to Turkey's decision to purchase Russia's S-400 air defense system, the fact remains that a substantial part of the US's nuclear arsenal is housed at Inçirlik Air Base — likely about 50 B61 gravity bombs.

The bombs have been housed there since the 1960s, The New Yorker reports. Even at that time, US officials worried about Turkey and other NATO members using the weapons without the permission or knowledge of the US. In the 1970s, when war between Greece (which also stores nuclear weapons) and Turkey seemed imminent, the US moved its nuclear stockpile from Greece and disabled the bombs in Turkey.

Experts have questioned the wisdom of having weapons housed in Turkey. In 2016, Jeffrey Lewis, director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies at Middlebury College, wrote of the weapons' uncertain security in the wake of a near coup that year.

"An airbase is a not a fortress; it is not intended to withstand a siege by the host government any more than an embassy might," Lewis wrote at the time, although the US has invested millions in upgraded security for its nuclear arsenal.

'It's not just about the security, it's that they serve no military purpose.'

According to Hans M. Kristensen, director of the Nuclear Information Project at the Federation of American Scientists, there are several potential scenarios for how the US's B61 arsenal at Inçirlik could be compromised.

"One involves relations with Turkey breaking down and interfering with the base operations, that is probably a wildcard," Kristensen told Insider via phone.

"The other scenario is a well-coordinated terror attack, causing havoc from inside," he said.

While the weapons are "very well-protected physically so it's hard to imagine coming in from the outside," the near-coup in 2016 saw F-16s at the base used to bomb the Turkish Parliament, and one of the alleged coup-plotters as the commander at Incirlik.

Kristensen noted that Incirlik is "radically different than any other nuclear storage site," given the political instability there and the increasingly poor relationship between the US and Turkey. If the weapons weren't already there, Kristensen said, it's unlikely that they'd be deployed in Turkey.

In terms of removing the weapons, logistically speaking it would be as simple as pulling up a couple of C-17s up to the base, loading the weapons in — likely under the cover of darkness to avoid attention — and flying them back to the US, Kristensen told Insider.

But politically, that's another matter entirely.

"A number of us have felt since the attempted coup in 2016 is that it's increasingly untenable to keep the weapons in Turkey," Jessica Varnum, Deputy Director of the James Martin Center for Nonproliferation Studies at Middlebury, told Insider.

The only way to avoid political fallout with Turkey would be to remove the US nuclear arsenal from all the NATO countries where they are stored.

"It's not just about the security, it's that they serve no military purpose," Varnum said of the weapons.

While the weapons were originally deployed to NATO member countries to demonstrate the US's commitment to the alliance against Russia and to prevent these allied nations from developing their own nuclear weapons, they're not useful in a real conflict, Varnum said, since it would take US assets far too long to get to the weapons to effectively use them.

"They're not particularly credible as a military threat, because of the timeline."

But after a week of chaos and threats from Erdogan, now may be the time to commit to taking the weapons out of Turkey, particularly after Turkey fired on a US position in Syria.

Last week, after the Pentagon confirmed that Turkey had fired at US positions in Syria, Lewis tweeted, "I think this is a first — a country with US nuclear weapons stationed in it literally firing artillery at US forces."