A U.S. Senate subcommittee approved a spending bill providing $351 million for Israel's Iron Dome program, double what the Obama administration requested. 

"It works," said Sen. Dick Durbin, chairman of the appropriations subcommittee.

The missile defense system has largely been credited with helping prevent a single Israeli casualty in the country's ongoing conflict with Hamas, shooting down an estimated 1,000 rockets fired into the country from Gaza with over 90 percent accuracy. 

The Iron Dome is made up of ten batteries, or locations equipped with rocket intercepter missiles and advanced radar tracking devices, and each missile fired costs around $50,000

In previous wars with Hamas in 2008 and 2009, Israel sent ground troops into Gaza, something that dramatically increased the death toll on both sides of the conflict. 

“If we did not have it and the rockets were falling in Israel, killing people, then the Israeli army would have little choice but to enter Gaza on foot to get rid of the place where the rockets are coming from,” former Israeli defense minister Amir Peretz and architect of the Iron Dome program told The Washington Post on Tuesday. 

The defense bill will provide $549.3 billion for the fiscal year beginning October 1, investing in development within the military as well as preventing the elimination of weapons programs the Pentagon proposed cutting including the A-10 Warthog, the close air support aircraft and the USS George Washington aircraft carrier.