For ten points, identify this final battle of the first Indochina War,  in which Vietnamese forces defeated a French garrison.
It wasn't in South America, but this battle's Operation Condor was a failed attempt by the GCMA to disrupt enemy supply chains. Troops were flown to the site of this battle in Operation Castor, and Charles Piroth committed suicide here with a hand grenade after failing to dislodge enemy artillery. The losing side at this battle underestimated their enemy after earlier winning at (*) Na San, and this loss for Christian de Castries was a victory for Vo Nguyen Giap ["vow win zyap"], a subordinate of Ho Chi Minh. For ten points, identify this final battle of the first Indochina War,  in which Vietnamese forces defeated a French garrison.
It wasn't in South America, but this battle's Operation Condor was a failed attempt by the GCMA to disrupt enemy supply chains.
Battle of Dien Bien Phu