Israel’s Iron Dome missile defense system is poised to receive a funding boost from the US based on a unanimous vote this week from the Senate appropriations subcommittee. The subcommittee voted on Tuesday to approve a requested increase in contributions to the system.

In March, Israel and the US signed an agreement in which the US would provide $175 million for the system in exchange for transferring more of the production to the US.  Then, Israel approached Capitol Hill asking to double the amount of funding in order to account for the greater cost of coproduction.  Prior to the agreement, only 3 percent of US funding was spent on parts manufactured in that country.  According to the deal, 30 percent of Iron Dome would be produced in the States in 2014, and 55 percent in 2015.

“The reason for this [request] is the impact of the cost of the transfer of production to the US, which was not part of the original proposed budget,” an Israeli Embassy official explained Monday.

The House Appropriations Committee, the House Armed Services Committee, and the Senate Armed Services Committee all approved the funding increase earlier this year.

Iron Dome was first deployed in southern Israel in 2011.  Since then, it has intercepted over 500 rockets fired at Israel, a success rate of nearly 90 percent.  Since it is expensive to deploy, at some $20,000 a rocket, the system is equipped with sensors that predict whether an incoming rocket is likely to hit a population center.  If it is headed to open territory, the system does not deploy.

In the current conflict alone, Operation Protective Edge, the Iron Dome has detonated 265 of the over 1,350 rockets lobbed at Israel. 1,027 of those rockets landed in Israel, majority in open territory.

Iron Dome is credited with bolstering public support for an extended air campaign against Gaza, rather than a riskier ground invasion.  To date, Israel has suffered only one death since Operation Protective Edge began July 8.

The additional $175 million still needs to be approved by the full committee, which will deliberate Thursday.  Having been approved by all other parties already, however, it is likely to pass.