One gets the strong impression from Thom Shanker’s profile that General Martin Dempsey, the new chairman of the Joint Chiefs of Staff, sees the writing on the wall on future military spending:

General Dempsey acknowledged an emerging truth about the size of the American military during the coming years: “I do think that we will be smaller,” he said. “But there are things we’ve learned over the last 10 years, capabilities that didn’t exist 10 years ago that exist today that can, for example, offset and mitigate the risk of a somewhat smaller conventional or traditional force.”
It is up to his two bosses, President Obama and Defense Secretary Leon E. Panetta, to decide with Congress how much money can be committed to national security and on the current missions that are no longer affordable.
General Dempsey said his task was “to articulate the risk that we face at certain levels of resourcing,” and he pledged to do that without “threat inflation or fear tactics.” [Emphasis added]

This struck me as an impressively sane way to think about the military budget. If I were trying to preserve as much military spending as possible, I imagine I’d take General Dempsey approach: acknowledge that there will decreases relative to the most ambitious plans for military spending, and try to control the tenor of the debate and its pace by trying to set the boundaries of what is and is not possible.