Some U.S. naval commanders are at odds with the Obama administration over whether to sail Navy ships right into a disputed area in the South China Sea — a debate that pits some military leaders who want to exercise their freedom of navigation against administration officials and diplomats trying to manage a delicate phase in U.S.-China relations.

The Pentagon has repeatedly maintained it reserves the right to sail or fly by a series of artificial islands that China is outfitting with military equipment. The Navy won’t say what it has or hasn’t done, but military officials and congressional hawks want the U.S. to make a major demonstration by sending warships within 12 miles of the artificial islands and make clear to China that the U.S. rejects its territorial claims.

By not doing so, they charge, Washington is tacitly accepting China’s destabilizing moves, which are seen by U.S. allies in the region such as Japan, the Philippines and Vietnam as highly threatening.

“We continue to restrict our Navy from operating within a 12 nautical mile zone of China’s reclaimed islands, a dangerous mistake that grants de facto recognition of China’s man-made sovereignty claims,” Sen. John McCain, the Republican chairman of the Armed Services Committee, told POLITICO.