Many of President Trump’s tweets are inexplicable. But when the president announces on Twitter he will veto bipartisan legislation to support the military because “THE BIGGEST WINNER OF OUR NEW DEFENSE BILL IS CHINA!,” it’s only natural to wonder what the heck he is talking about. I checked with more than a dozen administration officials, lawmakers and congressional officials to find out. The unanimous answer was, “No one knows.”

Trump knows, presumably. But the fact that neither his top national security officials nor the Republicans who are shepherding the National Defense Authorization Act (NDAA) through Congress even claim to understand why Trump is invoking China in this way is bizarre. The White House press office referred me to the National Security Council press office, which declined to comment and referred me back to the White House press office. None of the leaders of the House or Senate Armed Services Committees had any explanation to offer. China did not even earn a mention in the White House’s Statement of Administration Policy on the bill, released last week.

“Even White House staffers don’t know what his tweet is referring to because it’s not based in reality,” said Chip Unruh, press secretary for Senate Armed Services Committee ranking Democrat Jack Reed (R.I.). Either Trump was being irresponsible by not bringing up his China concerns until now, he said, or Trump is inventing them at the last minute, which could recklessly delay funding for the troops.

We do have some idea of why Trump doesn’t like the NDAA, which is one of the last remaining examples of bipartisanship to have survived Trump’s tumultuous term. Trump has fallen out with the Republican chair of the Senate Armed Services Committee, James M. Inhofe (Okla.), who led the Senate passage of the defense bill Friday (84-13) without jamming in a last-minute repeal of Section 230 of the 1996 Communications Act, as Trump had demanded. The president believes that might stop Twitter and Facebook from pointing out his false claims about the election, or at least punish them for it. Trump was also mad at Inhofe for not killing the NDAA’s provisions to rename military bases associated with the Confederacy.

Several Capitol Hill aides pointed out that adding a repeal of Section 230 to the defense bill at the last minute, as Trump wanted, was not likely possible anyway — entirely aside from the fact that it has nothing to do with the Defense Department. Many Republicans privately think Trump’s behavior is hurting the troops and their own party.

“The fact that Trump would veto pay raises for the troops, his own plan for a larger Navy and his own rebuild of the military over a provision in a law that no one has heard of isn’t just strategically stupid, it’s political malfeasance,” one senior GOP congressional aide told me.

Many believe Trump is trying to kill the defense bill out of spite. Trump was so mad at Inhofe, Axios reported, that last week he waved aside Inhofe’s objections to the United States recognizing Moroccan sovereignty over the Western Sahara, paving the way for Morocco to normalize relations with Israel. The White House killed the State Department authorization bill, included in the NDAA, this month in retaliation for Congress not including an Ivanka Trump legacy project.

But that still doesn’t explain why Trump is focusing his veto threat on China. Government and congressional officials were passing around several theories Monday. Some pointed out that Inhofe had tweeted Saturday the NDAA treated China as “our greatest threat,” and made clear to China “there is no quick and easy victory against us.” Trump may have seen that and taken the opposite view just to mess with Inhofe, this version goes.

Another theory making the rounds is that Trump was trying to link the repeal of Section 230 with China by arguing that the existing law enables tech firms to target U.S. politicians such as Trump while letting Chinese government propagandists off the hook. Some GOP lawmakers have made similar arguments. The argument doesn’t make sense, mostly because several countries’ officials, not just China’s, spread propaganda on Twitter — and such tweets are clearly flagged anyway.

No one discussing these theories claimed to know what Trump was really talking about. All of them believed he was wrong. In fact, this year’s NDAA includes lots of things Beijing won’t like, such as a new Pacific Deterrence Initiative and new measures to combat Chinese malign influence operations around the world. It also includes Trump’s own agenda items, including new ships for the Navy. It’s possible he is just being petulant.

“Everyone in Congress knows that Trump is threatening to veto a bipartisan defense bill because he’s mad at Twitter, mad that we’re renaming bases and generally mad about losing the election,” Rep. Tom Malinowski (D-N.J.) told me. “Those arguments didn’t work, so I guess he hopes that changing the subject to China will. But this is already the toughest NDAA ever when it comes to China, so that’s not going to cut it."

Meanwhile, the Chinese Embassy got caught last week retweeting Trump’s own election disinformation. Hilariously, the Chinese Embassy claimed its account was “hacked.” To believe that story, you would have to believe a hacker took the time to take over the Chinese Embassy’s Twitter account just to retweet one of Trump’s tweets — and then leave quietly.

China is not the biggest winner of the defense bill, as Trump asserted. But China is the biggest winner of our domestic infighting and our government dysfunction, both of which Trump insists on stoking during his final weeks in office.

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