Whether or not America's politicians can find a way to sidestep the brutal automatic military cuts of sequestration, the era of rising Western spending on weapons and wars is over.
That reality increasingly is challenging major arms manufacturers, spurring them to look for new markets, cost cuts and mergers. It is also confronting policymakers with difficult political and strategic choices as new rivals, particularly China, spend more on their armed forces.
U.S. military spending still dwarfs that of other countries - the equivalent of the next 13 nations' spending by some estimates - but the global military balance is clearly shifting. With European states already cutting, the London-based International Institute for Strategic Studies this year reported that Asian military spending outstripped Europe's for the first time in several centuries.
U.S. lawmakers may well avoid or delay automatic across-the-board budget cuts that would hit the military hard and are set to begin on January 2 if there is no deal on deficit reduction. But few see the United States avoiding military budget cuts in the next few years given that the government's debt burden has now surged above $16 trillion (9.95 trillion pounds) and continues to rise.
Republican presidential challenger Mitt Romney has pledged to increase Pentagon spending, particularly on the Navy. But he could find himself struggling to keep that promise if he defeats President Barack Obama next month.
U.S. strategic options may soon be defined more by what Washington can afford than by what it believes it needs.
"For the first time in our history, we may be facing a moment where we really do not have the money to do exactly what it is that the experts or the policy advisers ... suggest is the right thing," said Todd Harrison, senior fellow at the Centre on Strategic and Budgetary Assessments. "Budget cuts could end up determining the shape of U.S. policy."