Exactly what it is that Benedict Arnold did that branded him as a traitor to the US?

Arpeggionist

During the American Revolutionary War, Arnold intended to surrender, deliver, or sell West Point to the British, and all the new nation's military secrets with it. Mar 23 06, 3:10 PM

xfacilitatorx

In 1780, Arnold negotiated with British General Henry Clinton to hand over the American fort at West Point, New York to the British for £20,000 (about $1,000,000 today). Partially incapacitated, Arnold had used his leg injuries to secure a position as head of the fort at West Point. His plans were discovered when Major Andr� was captured on September 23, 1780 with incriminating documents in his boot. The capture of John Andr� was considered so significant that a special award, known as the Fidelity Medallion, was created by the Continental Congress for those who had participated in his capture. http://www.reference.com/browse/wiki/Benedict_Arnold http://www.reference.com/browse/wiki/Benedict_Arnold Mar 23 06, 5:12 PM

kingofcats

He handed westpoint to the british. Mar 23 06, 5:54 PM