Should automatic budget cuts to defense take place as planned on January 2, 2013, the White House calculates that the Pentagon will immediately lose $54.6 billion from its approximately $530 billion budget, every year for a decade. Those cuts will come from chopping approximately 9.4 percent out of almost everything the Pentagon does. It's a fiscal reduction the White House considers "deeply destructive" to national security, and may not be able to avoid.

That's the bottom line of the White House's dense new report on what's called "sequestration," a budgetary mechanism that's become both a doomsday clock inside the Pentagon and a political football on the campaign trail. The White House insists it "doesn't support" these budget cuts, mandated by a 2011 law: a "detailed statutory scheme" in the law forces the government to chop relatively equal percentages out of practically every defense program.

Yes, nearly every defense program, the sensible ones and stupid ones alike. The magic number for the Pentagon is 9.4. That's the percentage practically every defense program you can think of will lose – with the big, expensive exception of military pay and benefits – under what Defense Secretary Leon Panetta calls a "goofy, meataxe scenario." Basically, the budget mavens will have to go program to program, chopping 9.4 percent out of every one. For a military that prides itself in precision in targeting, this is a horror show. (A caveat: if Congress passes a funding bill called a Continuing Resolution in the coming weeks, the percentages will be readjusted.)

"Unless Congress acts responsibly," the White House report states, "there will be no choice but to implement them."

Stopping loose nukes under the Combined Threat Reduction Program? Subtract $65 million every year, for a decade – 9.4 percent. Funding the Afghan security forces, the cornerstone of the U.S. strategy to end combat in Afghanistan? Subtract $1.325 billion every year, for a decade – 9.4 percent. Safely destroying chemical weapons? Subtract $146 million every year, for a decade – 9.4 percent.

You get the idea. Shipbuilding; aircraft purchases; ammunition. Minus 9.4 percent; minus 9.4 percent; minus 9.4 percent. There are some other defense programs that get 10 percent cut, but relatively few. And some of the most expensive items in the defense budget are exempt, like military pay and healthcare. The Department of Veterans Affairs is also untouched.

"No amount of planning can mitigate the effect of these cuts," reads the White House report, released a week after a congressional deadline for the White House to spell out how it'd implement the cuts. "Sequestration is a blunt and indiscriminate instrument. It is not the responsible way for our Nation to achieve deficit reduction."

Sequestration is the result of a gambit from 2011's Budget Control Act. It was intended as a blunt instrument to force Congress into a wide-ranging compromise on reducing the deficit. Unless Congress found creative ways to trim $1.2 billion from the deficit over a decade – through a mix of tax hikes and program cuts – sequestration loomed as an automatic, 50/50 split, half of which took the cash out of the defense budget and the other half out of popular domestic programs. Since nobody wanted that, the Obama administration and congressional leaders reasoned, an enlightened compromise would result. Wrong.

Now it's a whole political thing. The Republicans want to lay the blame for sequestration on President Obama, whose White House came up with putting defense on the sequestration block last year. They want Obama to sign a bill they recently passed exempting defense from sequestration. The White House wants to lay the blame for sequestration on the Republicans, who came up with the Budget Control Act in the first place during a gamble over the debt ceiling and overwhelmingly voted for it. The White House opposes the GOP bill on the grounds that exempting defense from sequestration would put the burden of budget cuts on programs intended to help the sick, the old, the poor, and the schoolchildren. Expect to hear the dull buzzword "sequestration" frequently from Mitt Romney as he argues that Obama is out to slash defense. An actual solution to avert this disaster is MIA.

Meanwhile, the defense industry is freaking out over the prospect of lost contracts and is saying it'll have to lay people off ahead of the presidential election unless a compromise is found. Next week, the House Armed Services Committee plans a hearing to quiz Robert Hale, the Pentagon comptroller, on the looming automatic budget cuts, alongside the vice chiefs of the armed services – and now it has the White House's own explanation of the cuts to beat Hale over the head with.