United States President Barack Obama's announcement of significant shifts in US polices towards the Middle East and East Asia in 2009 has affected the global strategic landscape. President Obama's announcement of enhanced US engagement with Asia has posed certain challenges to the prevailing
regional architecture of ASEAN centric institutions and ASEAN centrality which has fostered peace and stability, and prosperity in the region. The rise of China and its growing political and economic influence in the region and its military modernisation have aroused US concern that a rising
China could in the future challenge its primacy in the Asia region. President Obama's announcement of a web of military alliances of treaty allies and strategic partners with the stationing of US marines in Darwin in November 2011 was perceived by China as an attempt by the US to contain China
or constrain its rise. ASEAN is uneasy about any emergence of big power rivalry in the region.