The main problem with the 'Asian circle' is not its population or its economic importance — which was initially great 200 years ago and is growing now. It is its manifest and lasting divisions. Like 19th century Europe whose Britain, France, Germany and Russia grew rapidly but eventually exploded in war, contemporary Asia is a region without unity. Europe eventually outgrew its divisions, but only after two world wars.
The rising countries in Asia are all rivals. As Taro Aso said, 'Japan and China have hated each other for a thousand years, what should be different now?' In this important sense there is no united 'East' to compare to the relatively coherent 'West' of today as America and Europe, already united militarily, plan to join in a new free trade zone. The Asian zone remains very important, but more for its conflicted economic growth than for its coherence.