I am struck by the juxtaposition of two news items. First, it is being reported that Bob Gates is proposing $100 billion in defense cuts over the next five years, including the cancellation of the Marines’ Expeditionary Fighting Vehicle. Second it is being reported that China’s military modernization program is moving ahead faster than expected. In recent days, China has unveiled a new stealth fighter, the J-20, and a new ballistic missile that has been dubbed a “carrier killer” because it is designed to target U.S. aircraft carriers. China is also reportedly building its own aircraft carriers and taking other actions to beef up its arsenal.

Granted, China has a long way to go before it approaches parity with the U.S. — but then again, it doesn’t need parity. Much of our military spending goes to enable operations thousands of miles from home. China, by contrast, seems to lack global ambitions, at least for the moment. It is concerned with dominating its region. And that does not require that it match U.S. military capacity across the board. All it has to do is raise the cost to the U.S. of taking action to keep in check Chinese expansionism, whereas the U.S. must worry not only about the threat from China but also about North Korea, Iran, al-Qaeda, Somalia, Yemen, and myriad other concerns.

The cuts proposed by Secretary Gates do not seriously threaten America’s military position in the world. Heck, I’ve expressed my own skepticism about the utility of the Expeditionary Fighting Vehicle. I am also not that alarmed about the cancellation of the F-22 or the pushing back of the Marine Corps’s vertical-takeoff version of the F-35; I think the Marine version of the F-35 could be canceled altogether, because the vertical takeoff and landing capability of the Harrier jump jet has so seldom been utilized in combat.

But I am concerned about talk of delaying or downsizing the overall F-35 program at a time when China and Russia are both fielding their own stealth fighters. More than that, I am worried that Gates’s cuts may be only the beginning of a drawdown that is happening even as we are still fighting a major war in Afghanistan. Already proposals are circulating — see, for instance, this Foreign Affairs article — for massive cutbacks, including the loss of hundreds of thousands of service personnel, that would eviscerate American power-projection capabilities. Alas, many in Congress, even some Republicans, appear to be open to deeper defense cuts.

I am all for addressing our runaway federal spending — but we won’t balance the budget on the back of the Defense Department. Not when defense spending is less than 20 percent of the budget and less than 5 percent of GDP. Getting our fiscal house in order requires cutting entitlement spending. Downsizing the military, by contrast, will contribute to future insecurity and turn out to be the most costly option in the long run. That is a lesson we should have learned in the past, many times over (as I argued in this op-ed).