Part of the small residual U.S. force that the Trump administration is keeping in Syria serves no real military purpose:

“Al-Tanf has no obvious military purpose,” added Sam Heller of the International Crisis Group. “The real justification is, to my knowledge, denying the Syrian government and its Iranian ally access to the neighboring al-Tanf/al-Walid border crossing with Iraq. That blocks a key trade route that would better integrate Syria with its regional surroundings and help government-held Syria get on a more stable economic footing, which some in DC believe would diminish U.S. leverage to force a political resolution to the war.”

The Tanf base represents a determination to retain a mostly symbolic military presence inside Syria if only to keep a small part of the country out of the Syrian government’s control. Keeping U.S. forces there accomplishes nothing for U.S. security, it is flagrantly illegal, and it puts these soldiers at risk for no good reason. Iran hawks desperately cling to this base because it is their last foothold in Syria from which to pursue their obsession with Iran.

In the latest twist, Trump has touted maintaining a military presence in Syria for the sake of “keeping the oil”:

President Trump said that he is planning to keep a small number of troops in northeast Syria to protect the oil fields there and suggested that an American company might help the Syrian Kurds develop the oil for export.

“I always said if you’re going in, keep the oil,” Mr. Trump said at a cabinet meeting Monday. “We’ll work something out with the Kurds so that they have some money, so that they have some cash flow. Maybe we’ll get one of our big oil companies to go in and do it properly.”

One of the only consistent features of Trump’s foreign policy views is his belief that other countries’ natural resources should be ours to seize and exploit as we please. Trump’s worldview is a bizarre mash-up of crude colonialism and racketeering in which allies are expected to pay protection money and open-ended military intervention is fine as long as it gets you paid. We have previously heard him express a desire to seize oil resources in Libya, Iraq, and Venezuela, and so it was inevitable that he would want to do the same thing with Syria.

Besides the obvious practical difficulties of controlling Syria’s oil fields with only a few hundred soldiers, there is the small matter of the sheer illegality of what Trump is proposing to do. Not only do our forces have no legal justification for being there and no authorization from Congress, but our government also has no right to sell this oil:

“Oil, like it or not, is owned by the Syrian state,” Mr. McGurk said Monday in an appearance at the Foundation for Defense of Democracies, a Washington think tank. “Maybe there are new lawyers, but it was just illegal for an American company to go and seize and exploit these assets.”

Mr. McGurk said that the only way to export the oil legally, the State Department concluded at the time, was to have an arrangement in which the money was put in escrow for use by the Syrians after the civil war was over, an arrangement that would have involved Russia and the Assad government.

That creates serious problems if there were an attempt to sell the oil from this area:

“It’s not really possible for us to exploit those oil resources unless we want to be oil smugglers,” McGurk said. He said that former Secretary of State Rex Tillerson, a long-time oil industry executive, had looked into helping the SDF sell Syrian oil, but could not find a legal path for American involvement without Assad’s permission.

Trump’s confused Syria policy is where his fascination with plunder and his obsession with Iran combine in a truly toxic mix:

Accordingly, it’s conspicuous that al-Tanf is what remains of the U.S. in Syria.

“It is everything wrong with Trump’s war in Syria,” said [Aaron] Stein. “The fact that it will be the last American enclave in Syria is more evidence of how Iran myopia has poisoned U.S. objectives in the region.”

There are U.S. troops that are still being kept in Syria for the worst and dumbest of reasons, and Trump is the one responsible for it.