An Independence Day fireworks display lights up the sky over Washington, as seen from the U.S. Marine Corps Memorial in Arlington, Virginia, July 4, 2012.

An Independence Day fireworks display lights up the sky over Washington, as seen from the U.S. Marine Corps Memorial in Arlington, Virginia, July 4, 2012.

Fireworks illuminate the night sky over the Washington Monument (bottom) during Fourth of July celebrations in Washington, DC, on July 4, 2012. Independence Day, commonly known as the Fourth of July, is a federal holiday in US commemorating the adoption of the Declaration of Independence on July 4, 1776, declaring independence from the Kingdom of Great Britain.

Fireworks illuminate the night sky over the Washington Monument and the Capitol Dome (bottom) during Fourth of July celebrations in Washington, DC, on July 4, 2012. Independence Day, commonly known as the Fourth of July, is a federal holiday in US commemorating the adoption of the Declaration of Independence on July 4, 1776, declaring independence from the Kingdom of Great Britain.

Fireworks light up the sky over the Philadelphia Museum of Art during an Independence Day celebration, Wednesday, July 4, 2012, in Philadelphia.

Fireworks explode over the Philadelphia Museum of Art and a statue of George Washington during an Independence Day celebration, Wednesday, July 4, 2012, in Philadelphia.

BAUMHOLDER, GERMANY - JULY 04: U.S. soldiers and their families watch fireworks during the 4th of July festivities at the Baumholder U.S. military base on July 4, 2012 in Baumholder, Germany. Baumholder has traditionally been home to the 170th Infantry Brigade, though the unit, which numbers several thousand soldiers and has participated in numerous combat operations in Afghanistan, will be inactivated by the fall of 2012 and its members and their families redeployed, mostly back to the United States. The move is part of a broader cost-cutting effort by the Pentagon, though it does not mean the end for the Baumholder garrison, as other U.S. military units are currently being gradually transferred to it.

BAUMHOLDER, GERMANY - JULY 04: U.S. soldiers and their families watch fireworks during the 4th of July festivities at the Baumholder U.S. military base on July 4, 2012 in Baumholder, Germany. Baumholder has traditionally been home to the 170th Infantry Brigade, though the unit, which numbers several thousand soldiers and has participated in numerous combat operations in Afghanistan, will be inactivated by the fall of 2012 and its members and their families redeployed, mostly back to the United States. The move is part of a broader cost-cutting effort by the Pentagon, though it does not mean the end for the Baumholder garrison, as other U.S. military units are currently being gradually transferred to it.

BAUMHOLDER, GERMANY - JULY 04: U.S. soldiers and their families watch fireworks during the Fourth of July festivities at the Baumholder U.S. military base on July 4, 2012 in Baumholder, Germany. Baumholder has traditionally been home to the 170th Infantry Brigade, though the unit, which numbers several thousand soldiers and has participated in numerous combat operations in Afghanistan, will be inactivated by the fall of 2012 and its members and their families redeployed, mostly back to the United States. The move is part of a broader cost-cutting effort by the Pentagon, though it does not mean the end for the Baumholder garrison, as other U.S. military units are currently being gradually transferred to it.

BAUMHOLDER, GERMANY - JULY 04: U.S. soldiers and their families watch fireworks during the 4th of July festivities at the Baumholder U.S. military base on July 4, 2012 in Baumholder, Germany. Baumholder has traditionally been home to the 170th Infantry Brigade, though the unit, which numbers several thousand soldiers and has participated in numerous combat operations in Afghanistan, will be inactivated by the fall of 2012 and its members and their families redeployed, mostly back to the United States. The move is part of a broader cost-cutting effort by the Pentagon, though it does not mean the end for the Baumholder garrison, as other U.S. military units are currently being gradually transferred to it.