There's nothing like a whiff of possible resurgent militarism from the Land of the Rising Sun to get people - on both sides of the Pacific - to sit up and pay attention. Yet Tokyo's assertion this week that it may choose to deal with the North Korean ballistic missile threat using pre-emptive military strikes doesn't mean we should now call Japan the "Land of the Rising Gun."

Sure, Japan's tough stance on North Korea's missile tests is a bit unexpected from a country whose constitution has forbidden military action for other than self-defense since the end of World War II. But some of the seven North Korean missiles did fall within 200 miles of Japanese territory. And since 1993, North Korea has lobbed a number of missiles over Japan into the Pacific Ocean. Worse yet, at some point, Japan - and the 40,000 U.S. forces stationed there - might be faced with the prospect of a medium-range North Korean No Dong missile armed with a nuclear warhead heading in their direction.

But what most haven't divined about Japan's mercurial reaction is that its stance is more than just a shot across the bow of the irascible North Koreans. It was really aimed at China. Just as it did with Iran's nuclear program, China has been running interference for the North Koreans in the U.N. Security Council, refusing to take either country to the woodshed over their wayward behavior. But there's an important distinction. While China has been cozying up to Iran to satiate its nearly endless hunger for oil and gas and to protect its $100 billion investment in Tehran's energy infrastructure, it really has limited direct influence with Iran beyond the United Nations.

North Korea, though, is a different story. Beijing has clout in Pyongyang. In fact, China has more pull in North Korea than anyone else, including the United States and South Korea. China is North Korea's largest aid donor. Beijing provides impoverished Pyongyang with food, crop fertilizer and fuel oil to run what is left of North Korea's crippled economy.

In the past, China has stopped aid shipments to show its displeasure with its pesky Communist cousin. In 2004, it shut off the fuel spigot to force Pyongyang back to the nuclear negotiating table.

North Korea and China are allies, too. Remember the Korean War? No reminder is necessary if you were around when 200,000 Chinese swarmed over the Yalu River into North Korea in 1950.

So what does this have to do with Japan?

Tokyo is playing on the fact that China serves as North Korea's biggest benefactor/protector. If you want to get Pyongyang to play nice, pressure its Sugar Daddy, Beijing.

And, arguably, nothing spooks China more than a remilitarized Japan. Even less appealing is a provoked Tokyo operating independently of the U.S.-Japan alliance. Plus Beijing, with its own grand ambitions, doesn't want to inflame its budding rivalry with Japan, already powerhouse in its own right.

So, when Beijing, not surprisingly, opposed Tokyo's tough resolution on North Korea at the United Nations, effectively tabling the matter, Japan decided to raise the ante by hinting it would take matters into its own hands. Realizing that Japan was serious about the North Korean threat, China quickly dispatched a high-level diplomatic team to discuss matters with North Korea's "Dear Leader," Kim Jong Il.

No surprise that North Korea's initial public reaction was more defiance, embarrassing the Chinese. But it's likely that Beijing will be able to eventually talk North Korea back from the abyss, undoubtedly using some arm-twisting.

Whether Japan will actually reinterpret its pacifist constitution to deal with North Korea is conjecture at this point. But the gambit got China's attention - and will continue to motivate Beijing to curb Pyongyang's perfidy.

Peter Brookes, a senior fellow at The Heritage Foundation, is the author of "A Devil's Triangle: Terrorism, WMD and Rogue States."