The US sends China a message with a couple of B-52 bombers

An already tense standoff between China and Japan took a turn for the worse over the weekend when China declared a new "air defense identification zone" in the East China Sea. China is demanding that all flights receive prior approval before entering the zone.

The response from Washington was swift. First came the rhetorical pushback. A White House spokesman called the Chinese move "unnecessarily inflammatory." Secretary of State John Kerry condemned China's "escalatory action." And, at the Pentagon, defense chief Chuck Hagel issued a sharp statement:

"We view this development as a destabilizing attempt to alter the status quo in the region. This unilateral action increases the risk of misunderstanding and miscalculations."

Then came the B-52s. They were unarmed and the Pentagon said the flight plan had been in place for some time. But the bombers entered airspace now claimed by China in a blatant challenge to the Chinese government's new edict. This was a clear message from the US military.

The flight went off without a hitch.

China responded by saying it tracked the American bombers, and it appeared to back down slightly by loosening some of its initial demands for aircraft flying through the designated area. But tensions remain high, with China dispatching an aircraft carrier to the region.

The chances of an all-out military conflict between China and Japan are slim. China's military capability might be growing by leaps and bounds, but it still remains far outmatched by US military power in the Asia Pacific. The Japanese constitution also essentially prohibits it from engaging in offensive military action.

Some experts say China might have miscalculated, overplaying its hand and underestimating how quickly the US and its allies would respond. Michael Green of Georgetown University said that the Pentagon made the right move by sending those B-52s into China's newly declared "air defense identification zone."

At The Atlantic, James Fallows – a former China correspondent for the magazine and a pilot himself – has a great post on how to think about all this, including a map of the airspace around North America. Also, a hat-tip to Fallows for steering us toward this satirical Taiwanese animated take on the whole affair.