Some of the first words and some of the last words to come up in this week's presidential debate were about military spending. President Barack Obama repeatedly hit Mitt Romney for supposedly wanting to spend $2 trillion in new defense dollars; money, he asserted, that the armed forces haven't asked for and Romney hasn't explained how he would spend.

"Politicians who mistake perceived war fatigue among citizens with their supposed desire for letting go of over a half century of military superiority in favor of decline are probably not making a safe bet." -Mackenzie EaglenPresident Obama has run TV ads in battleground states highlighting that GOP presidential nominee Romney wants to increase military spending. This tracks with statements by former President Bill Clinton during the Democratic National Convention this summer. Clinton said that Republicans "want to actually increase defense spending over a decade $2 trillion more than the Pentagon has requested, without saying what they'll spend it on."

While President Obama clearly thinks it is good politics to run against a smaller defense budget, Mitt Romney believes fundamentally in peace through strength and credible, unquestionably strong military forces to reinforce American power. The key difference is that Obama is focused on numbers while Romney is focused on what those numbers provide the nation in terms of prosperity and economic output due to avoiding conflicts, influencing events in our favor, and successfully empowering diplomatic and other "whole of government" efforts abroad.

Politicians who mistake perceived war fatigue among citizens with their supposed desire for letting go of over a half century of military superiority in favor of decline are probably not making a safe bet. Many voters intuitively understand that when our economy is weak it is not the smartest time to also weaken our military strength since the two underpin each other in many ways.

Since the end of World War II, the United States has played a comprehensive and active role globally with a view toward anticipating and managing risk to protect freedom while preventing another general war. Securing national objectives without fighting is cheaper and safer for our military but also better for our economic strength and growth in the long-run. Over the last half century, America has enjoyed the benefits of an era of general peace and prosperity where freedom has flourished. The foundation of that economic prosperity has been the decisive predominance of American power, beginning with its military strength. The sacrifice necessary to sustain that power is modest, and the risks of failing to do so are enormous.

On this issue, the voters may just surprise the president and side with a vision of strength more closely aligned with that of Romney. When it comes to defense, a little investment can go a long way.

Mackenzie Eaglen is a resident fellow in the Marilyn Ware Center for Security Studies.