From the History Channel:

Although the term D-Day is used routinely as military lingo for the day an operation or event will take place, for many it is also synonymous with June 6, 1944, the day the Allied powers crossed the English Channel and landed on the beaches of Normandy, France, beginning the liberation of Western Europe from Nazi control during World War II. Within three months, the northern part of France would be freed and the invasion force would be preparing to enter Germany, where they would meet up with Soviet forces moving in from the east.

With Hitler's armies in control of most of mainland Europe, the Allies knew that a successful invasion of the continent was central to winning the war. Hitler knew this too, and was expecting an assault on northwestern Europe in the spring of 1944. He hoped to repel the Allies from the coast with a strong counterattack that would delay future invasion attempts, giving him time to throw the majority of his forces into defeating the Soviet Union in the east. Once that was accomplished, he believed an all-out victory would soon be his.

On the morning of June 5, 1944, U.S. General Dwight D. Eisenhower, the supreme commander of Allied forces in Europe gave the go-ahead for Operation Overlord, the largest amphibious military operation in history. On his orders, 6,000 landing craft, ships and other vessels carrying 176,000 troops began to leave England for the trip to France. That night, 822 aircraft filled with parachutists headed for drop zones in Normandy. An additional 13,000 aircraft were mobilized to provide air cover and support for the invasion.

For 25 years bikers have descended upon Washington DC to show their support for the troops and to remind the world that our fallen will not be forgotten.  The ride culminates at the Vietnam Memorial Wall and has grown each year.

Rolling Thunder is an annual motorcycle rally that is held in Washington, DC during the Memorial Day weekend to call for the government's recognition and protection of Prisoners of War (POWs) and those Missing in Action (MIAs). The tribute to American war heroes started out in 1988 with 2,500 participants. Now approximately 900,000 participants and spectators are involved with this annual demonstration in Washington, DC. Rolling Thunder celebrates its 25th anniversary this year with expanded programming. By Rachel Cooper, About.com Guide

There is one particular hero that has committed himself to showing his respect and honor for those that have served and those that have participated in Rolling Thunder.  For the last ten years former Marine SSgt Tim Chambers has stood in full Marine dress saluting every bike that passes as they enter Washington DC.  He has held his salute until the very end.  Oh, his arm may dip, but never does he drop his salute.  He is a hero for those that see him. 

Watch these videos of SSgt Chambers and you will see how strong and determined he is.  Semper Fi SSgt Chambers

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