There is, in short, a lot of rhetoric being thrown about, partly because the military is at what President Obama has called "a moment of transition." After 11 years of post-9/11 budget increases, followed by an end to the intervention in Iraq, the U.S. military has suddenly lost its political immunity from the austerity pressures afflicting other parts of the government.

ABOVE: National security spending went up by nearly two-thirds over the last decade, driven partly by the wars in Iraq and Afghanistan and post-9/11 security anxieties. But the Pentagon has lost its political immunity.

The debate over how much to invest in national security will pick up speed in coming weeks, when the administration provides new details of its cuts to Capitol Hill, but it will persist throughout this presidential election year. So, as a service to our readers, we offer the following field guide to the defense budget debate:

The Obama administration is talking about taking hundreds of billions of dollars away from the military. Is this a major cut?

Actually, describing it as a cut is a misnomer. The plan actually calls for an increase in the national security budget over the next decade -- but it would scale back the 18 percent boost previously set for that period.

As Obama made clear in a brief speech while standing with Panetta on January 5, "the growth in the defense budget will slow, but the fact of the matter is this: It will still grow."

Here's the backdrop: Between 2000 and 2009, the average annual growth in national security budget authority was around 6 percent. That made spending go up by around two-thirds, to nearly $720 billion. Today, national security accounts for more than half of so-called "discretionary" spending -- the portion decided annually by Congress.

Before Obama announced his plan, the Pentagon was counting on an annual boost over the next 10 years. While there may be a net decrease in spending over the next year, the budget will soon revert to net increases, administration officials say. They have not said what the average annual increase will be if Congress approves his trims, but two senior administration officials who asked not to be named said the result after 10 years will still be a larger budget, even after inflation is taken into account.

That means Obama's proposed changes will shift such spending less than one percent annually. If approved, the change would be much smaller than the genuine reductions that followed the Korean War (20 percent), the Vietnam War (30 percent) and the Cold War (30 percent).

So what's going to be changed, exactly?

Pentagon officials have said they will release the details beginning this afternoon. But deputy defense secretary Ashton Carter has already explained that the military will not retain "the large force structure necessary to sustain long, large-scale stability operations" like the incursions in Iraq and Afghanistan. He also said "we are obviously going to have less modernization" and as a result, the Pentagon would "stop certain things, pause certain things, slow down certain things."