The measure was originally part of a package intended to fund the handling of the humanitarian crisis at the U.S. southern border, which failed to pass the Senate Thursday night.
Sen. Tom Coburn, R-Okla., blocked the bill when it was part of the larger $2.7 billion border package, demanding the $225 million be offset. But by Friday, he relented, and the aid was passed by unanimous consent after most members had left Washington for August recess.
"By passing this bipartisan measure, we send a message to Hamas that its terrorist tactics and its attempts to terrorize Israel's populace will not succeed," said Minority Leader Mitch McConnell, speaking in support of Israel in its ongoing fighting in Gaza.
"As a treasured ally, it's important that we enable Israel to guard themselves against Hamas," added Appropriations Committee Chairwoman Barbara Mikulski, who with Reid and McConnell sponsored the bill.
The funding would be added to the $700 million the U.S. has already contributed to Iron Dome, which uses an advance system of radar and missile tracking to follow incoming rockets. When a rocket is detected, the system determines if it is aimed at a population center, in which case it would fire an interceptor from a battery of launchers placed throughout Israel, detonating the rocket mid-air.
Israeli officials say the system has a success rate as high was 90 percent, and has significantly reduced the number of civilian casualties suffered by Israel. It was developed after the war against Lebanon in 2006, when Hezbollah fired nearly 4,000 rockets into northern Israel and killed 44 civilians. It was put into effect in 2011.