China's A2/AD has already put that power into question whether some want's to agreed or disagreed, but it has already caused the Pentagon lost of sleep knowing a confrontation with China will be extremely costly both diplomatically, militarily, and economically.The world keeps turning so it's an ongoing effort. Containment is just a euphemism for strangulation-rather-than-bash-their-skull-in, so the goal has not been achieved yet. The threat is any potential to challenge whatever the powers-that-be want to do, especially when what they want to do is particularly unfair, unreasonable, and harmful to others.
Hard power example - the US military pivot to Asia which is very real, significant, and effective despite domestic political bashing often heard in this forum. More of the best of the best military in the world, the most cutting edge equipment of all stripes, will be based in Asia. A slew of arms deals and military exchanges not just to improve the military capabilities of a number other Asian countries but also to influence those militaries to prime them for an anti-China alliance even if informal. China's maritime geographical disadvantage has already long been exploited with the annexation and militarization of the Ryukyus, support for the Taiwan military, foreign naval basing in the Philippines and possibly Vietnam, and the fact that China is in such a disadvantageous physical position in the Spratlys which it is trying to ameliorate with building on its holdings.
As for soft power China pretty much already have free trade agreement with South Korea, Australia, and many of it's Asian neighbors that put the TPP to shame. The South Korea and Japanese agreement to the past Japanese Agression during WW2 will further increase China's stance on Japan's holocaust in China. This will open up more Asian nations to push for Japan to accept their past aggression and wrong doing during WW2.