New US Fourth Fleet raises question: gunboat diplomacy?

The United States has watched with concern as leftists have been elected to power in a string of Latin American countries, sometimes with an assist from oil-rich Venezuela and its vehemently anti-American President Hugo Chavez.
Venezuela's acquisition of high performance fighter aircraft, attack helicopters, and diesel submarines also have raised flags for the US military.
But since becoming head of the US Southern Command in 2006, Admiral James Stavridis has taken a soft power approach to the region, pushing exercises, port visits and humanitarian missions to better US relations.