The presence of those American bases in Saudi Arabia were used by Osama Bin Laden to recruit people to die on 9/11 because they considered a base by infidels in their country blasphemy. Those bases had been left there after the first Gulf war. After 9/11, Bush quietly closed those bases but he did so quietly so not to interfere with his farcical explanation for invading Afghanistan and Iraq ... . "They Hate Our Freedums"
Donald Trump reopened those bases and I'm convinced he did that on purpose to stimulate another 9/11 because he saw how the first 9/11 ended up giving Bush such glowing poll numbers. (don't pretend for a second that Trump isn't contemptible enough to do such a thing). Trump even gave a speech early in his administration to the effect that the only way this nation would unite behind him was another event like 9/11.
Biden should have closed those bases on day one.