FOR under an hour, a pair of unarmed B-52 bombers flew unannounced over China's newly declared Air Defence Identification zone (ADIZ), prompting questions whether the United States had decided to take a tougher line with China.
Until the events of the past few days, the US preferred to coax and persuade, rather than threaten, in its engagement with China.
The accepted thinking among experts about the way forward for the US was to try and make China a stakeholder in global problems.
In fact, at a forum on The Future of American Defence organised by the Aspen Institute, a think-tank, just before news broke of the bombers' flight, analysts again proposed this inclusion as the best option for the US.
But Ms Michele Flournoy, former US undersecretary of defence for policy, told the panel discussion: "We need to have some hedge in our strategy against the possibility that China may choose to compete or to use military force to pursue its interest in the future, and we need to make sure that we have a military that can operate effectively in the face of that.
"But we want to do that in a way that is not feeding or fuelling its more competitive dimensions. But that is a very fine line to walk."
Whether that line has been crossed by the B-52 bombers remains up in the air, although some say the evidence now points more towards a competition.
Brookings Institution non-resident senior fellow Marvin Kalb wrote online that the current shift away from the use of force might not be an effective strategy.
"President (Barack) Obama clearly wants to accent diplomacy and lean no longer on military action, which seemed to be American policy in the last decade," he said.
"But China casts a huge shadow over his strategic deliberations, raising questions about whether his preference for diplomacy can work in Asia, specifically in the East China Sea."