Up until last week, we could classify the threats to Davis-Monthan Air Force base as medium-term but gathering.

Yes, some in the Air Force were recommending that the A-10 be retired before its expiration date in the 2020s, but that threat was in the Defense bureaucracy and would take time to materialize.

Then Secretary of Defense Chuck Hagel spoke Feb. 24, and the threat got real.

He proposed to retire all of the A-10s to achieve a savings of $3.5 billion over five years.

“The ‘Warthog’ is a venerable platform, and this was a tough decision,” Hagel said in a prepared statement. “But the A-10 is a 40-year-old single-purpose airplane originally designed to kill enemy tanks on a Cold War battlefield. It cannot survive or operate effectively where there are more advanced aircraft or air defenses.”

Just like that, there is a short-term threat to the three A-10 squadrons — two active-duty and one reserve — that are the heart of D-M’s existence and key to our local economy. And suddenly our need to fight to preserve D-M’s current mission and find alternative missions over the medium and long terms became that much more urgent.

For now, the A-10 has a one-year lease on life. The National Defense Authorization Act for this year makes it illegal for the Defense Department to spend any money to “retire, prepare to retire, or place in storage” the A-10.

It’s pretty clear that Hagel and Co. violated this portion of the law. How did they come up with the proposal to retire the A-10 without violating it? But I don’t expect the U.S. Capitol police to jail him any time soon.

In the next few months, discussions will begin on the 2015 National Defense Authorization Act. U.S. Rep. Ron Barber, D-Ariz., told me Tuesday he’ll work with Sen. Kelly Ayotte, who spearheaded the effort to preserve the A-10 in the U.S. Senate last year, to do it again.

“We can repeat that, and we’ve been talking about doing that again in the new NDAA that will be coming up in the next couple of months,” said Barber.

Ayotte is a Republican from New Hampshire who doesn’t have a dog in the fight except that her husband was an A-10 pilot. She and the many other supporters of the A-10 simply think it’s the only aircraft that can optimally carry out “close-air support” of troops on the ground, and they argue the new F-35 is not up to that task.

From Barber’s point of view, the real culprit in the A-10 issue is “sequestration,” the budget gimmick that went into effect at the beginning of last year, causing automatic cuts in federal spending and forcing the military to act quickly.

“Without the sequestration problem, we wouldn’t even be having a conversation about the best close-air support aircraft we have in the Air Force,” he said.

His focus for now is on preserving D-M’s missions over the short-term, more than pursuing the long-term alternatives we’ll eventually need.

Barber’s chief opponent on the Republican side, Martha McSally, is a retired A-10 pilot and faults Barber for not recognizing the danger early enough, noting that he told me last August that there weren’t short-term threats to the A-10. The Air Force chief of staff gave a speech in June 2013, McSally said, in which he said the service was looking to retire the A-10.

“The Air Force has been deliberately trying to slowly kill the A10 for the last several years,” she said. “The risk was obvious if he had investigated further.”

In fact, on Feb. 21 the Air Force quietly put the 358th fighter squadron at D-M on inactive status, replacing it with a reserve squadron that naturally doesn’t have the same impact as an active-duty unit, McSally noted.

Barber said the critique is off-base and that he’s been supporting the A-10 since he was district director for his predecessor, Gabrielle Giffords.

The threat isn’t to Davis-Monthan’s existence as an Air Force base, at least not for now. First of all, there is no Base Realignment and Closure process underway or planned by Congress. Second, the Aircraft Maintenance and Regeneration Center, better known as the “boneyard,” is a crucial facility at D-M.

“It would be a major effort to move it,” said Mike Grassinger, who is president of the DM 50, a local nonprofit group that supports the base. But he added that for Tucson, “The worst possible situation would be to close everything else and have the boneyard open.”

That’s because the boneyard would need a runway to bring in airplanes, meaning the base could not be redeveloped for a new use but would have relatively little day-to-day use or economic impact.

So we’re back to the task of keeping the A-10 mission intact as long as possible. What’s new is that the timeline has shortened for finding alternatives to replace it. Whether it’s landing the F-35 or some other mission that may be more compatible with the urban environment here, D-M’s importance to Tucson requires that we do that work.