USS Arizona Memorial, Pearl Harbor, Honolulu, HI

The USS Arizona Memorial, located at Pearl Harbor in Honolulu, Hawaii, marks the resting place of 1,102 of the 1,177 sailors killed on the USS Arizona during the Attack on Pearl Harbor on December 7, 1941 by Japanese imperial forces and commemorates the events of that day. The memorial, dedicated in 1962, is visited by more than one million people annually. (Photo by Ronen Zilberman/Getty Images)

Vietnam Veterans Memorial, Washington, DC

(Photo by Mandel Ngan/AFP/Getty Images)

A visitor to the Vietnam Veterans Memorial is reflected on the surface of the wall in Washington, DC. The memorial honors US service members of the US armed forces who fought in the Vietnam War, service members who died in service in Vietnam/Southeast Asia, and those service members who were unaccounted for (Missing In Action) during the War.

National D-Day Memorial, Bedford, VA

The Blue Ridge Mountains can be seen behind a sculpture titled 'Final Tribute' at the National D-Day Memorial, Bedford, Virginia. The memorial was dedicated in 2001 honoring American GIs who participated in the invasion of France at Normandy on June 6, 1944, during World War II. Bedford, Virginia was chosen for the memorial site because the town lost 19 of its men that day, all were members of Company A, 29th Infantry Division. (Photo by Mark Wilson/Getty Images)

Arlington National Cemetery, Arlington, VA

A man stands in front of a grave at Arlington National Cemetery in Arlington County, Virigina. More than four million people visit the cemetery annually, many coming to pay final respects at graveside services, of which nearly 100 are conducted each week. (Photo by Brendan Smialowski/Getty Images)

Gettysburg National Military Park, Pennsylvania

This is one of the 1200 memorials which dot the Gettysburg National Military Park in Gettysburg, Pennsylvania. This battle memorial is along Cemetery Ridge, the site of Pickett's Charge, an infantry assault ordered by Confederate Gen. Robert E. Lee against Maj. Gen. George G. Meade's Union positions on Cemetery Ridge on July 3, 1863, the last day of the Battle of Gettysburg during the American Civil War. (Photo by Tim Sloan/AFP/Getty Images)

US National World War II Memorial, Washington, DC

Tourists visit the World War II Memorial on the National Mall in Washington, DC. Dedicated to Americans who served in the armed forces and as civilians during World War II, the memorial consists of 56 pillars and a pair of arches surrounding a plaza and fountain. (Photo by Karen Bleier/AFP/Getty Images)

Liberty Memorial, Kansas City, MO

President Barack Obama speaks at a rally during his presidential campaign in 2008, at the Liberty Memorial in Kansas City, Missouri. The Liberty Memorial is a memorial to the fallen soldiers of World War I and houses the The National World War I Museum, as designated by the United States Congress in 2004. (Photo by Emmanuel Dunand/AFP/Getty Images)

Shiloh National Military Park, Savannah, TN

The 14-foot tall $250,000 bronze sculpture called 'Passing of Honor', located at the Shiloh National Military Park, is the first official Tennessee memorial to Tennessee Confederates who fought and died at Shiloh. The sculpture depicts a sergeant taking a Confederate flag from the hands of a dying soldier while another stands guard over them. (Photo credit: National Park Services)

National Memorial Cemetery of the Pacific, Honolulu, HI

A US Marine ceremonial rifle team stand at attention during a memorial ceremony at the National Memorial Cemetery of the Pacific in Honolulu, Hawaii. Located in Punchbowl Crater, the cemetery serves as a memorial to those men and women who served in the United States Armed Forces. Thousands of visitors visit the cemetery each year, and it is one of the more popular tourist attractions in Hawaii. (Photo by Marco Garcia/Getty Images)

Marine Corps War Memorial (Iwo Jima Memorial), Arlington, VA

A US Marine Corp firing party practices in front of the Iwo Jima Memorial in Arlington, VA. The memorial depicts the famous flag raising on the island of Iwo Jima during World War II, and is dedicated to all personnel of the United States Marine Corps who have died in the defense of their country since 1775. (Photo by Karen Bleier/AFP/Getty Images)

Arlington West, Santa Monica, CA

A view of crosses marking soldiers lost during the war in Iraq is seen at Arlington West on Santa Monica Beach, California. Each Sunday, from sunup to sundown since 15 February, 2004, the temporary memorial is erected in the sand just north of the pier at Santa Monica Beach by the local chapter of Veterans for Peace (VFP) and other volunteers. (Photo by Gabriel Bouys/AFP/Getty Images)