It is useful to observe that the world is changing quickly and America's influence is different than it was, but the derogatory note is distracting. Obama is a weak leader, as was Bush, Clinton etc. A strong leader will not get elected in today's America. But America does have strong leadership, in the form of hundreds of lobbies and special interest groups that tug the weakened president in 100 conflicting directions.
Saudi-led coalition air strike kills around 30 Yemeni civilians (Reuters)
from the article: WikiLeaks cables tell the story of an empire in decline