It has put countering Beijing, along with Russia, at the centre of a new national defence strategy.
Defence Secretary Jim Mattis anticipates 'bumpy road' ahead in talks with Pyongyang.
It is seen as an attempt to counter China's efforts to limit freedom of navigation in the strategic waters.
Despite growing US ties to China in a bid to quell North Korea, the US Navy still warns off China's claims in SE Asia.
It’s the largest non-nuclear device it has ever unleashed in combat.
This is likely to raise questions about whether and how the United States will respond.