President Barack Obama, seen here before delivering remarks on wind power at the Heil Family Farm in Haverhill, Iowa in August 2012, blocked a Chinese-led group from purchasing several wind farms near... more 

President Barack Obama, seen here before delivering remarks on wind power at the Heil Family Farm in Haverhill, Iowa in August 2012, blocked a Chinese-led group from purchasing several wind farms near a US naval station, saying the acquisition threatened the country's national security less