BLUFFTON, S.C. — Republican presidential hopeful Jon Huntsman says opponents Herman Cain and Mitt Romney raise concerns about misguided policy in their comments on dealing with China.

The former Utah governor and ambassador to the Asian nation says Wednesday that what GOP opponents don't know about security and trade involving China can be damaging to the United States.

In a PBS interview this week Cain said China is trying to develop a nuclear capability. China detonated its first nuclear device in 1964. Huntsman says candidates need to be knowledgeable and clear-minded about China's military.

Huntsman said Romney's call for tariff retaliation against China's currency manipulation would spark a trade war.

Cain and Romney have been leading the GOP field while Huntsman's campaign has sputtered.