These are tough times for military recruiting. Almost across the board, the armed forces are experiencing large shortfalls in enlistments this year — a deficit of thousands of entry-level troops that is on pace to be worse than any since just after the Vietnam War. It threatens to throw a wrench into the military’s machinery, leaving critical jobs unfilled and some platoons with too few people to function.

Covid-19 is part of the problem. Lockdowns during the pandemic have limited recruiters’ ability to forge bonds face to face with prospects. And the military’s vaccine mandate has kept some would-be troops away.

The current white-hot labor market, with many more jobs available than people to fill them, is also a factor, as rising civilian wages and benefits make military service less enticing.

But longer-term demographic trends are also taking a toll. Less than a quarter of young American adults are physically fit to enlist and have no disqualifying criminal record, a proportion that has shrunk steadily in recent years. And shifting attitudes toward military service mean that now only about one in 10 young people say they would even consider it.