On 29 June, U.S. warplanes began bombing Hanoi, capital city of North Vietnam. By 31 December, 385,000 U.S. troops were stationed in South Vietnam. An additional 60,000 troops were stationed offshore and another 33,000 in Thailand.
Richert, Lucas Paul. "U.S. bombs Hanoi and begins troop build-up". The Literary Encyclopedia. First published 01 November 2008
[http://www.litencyc.com/php/stopics.php?rec=true&UID=5668, accessed 31 May 2016.]