U.S. funding for Israel's Iron Dome counter-rocket system, a key component of the country's developing missile defense shield, could be reduced because of severe defense spending cuts.

"Iron Dome will be cut," U.S. defense industry consultant Randy Jennings, a former congressional aide on defense issues, said at a Heritage Foundation conference in Washington.

Jennings cautioned: "There will be no sacred cows ... All the programs will be hit." Iron Dome is the short-range anti-rocket system built by Israel's Rafael Advanced Defense Systems.

The Jerusalem Post observed: "Jennings was referring primarily to the looming threat of 'sequestration,' whereby some $100 billion of next year's U.S. budget will automatically be cut across the board, starting in January, unless a gridlocked Congress works out major compromises before then."

The prospect of severe funding cuts for the Iron Dome program, largely aimed at paying for additional batteries to reinforce the four deployed around Israel, could have a serious effect on Israel's drove to build a four-tiered missile defense shield.

That is primarily designed to counter everything from Iranian and Syrian ballistic missiles down to short-range rockets such as those used by Palestinian militants in the Gaza Strip and Hezbollah in Lebanon.

Israel is racing to prepare for an unprecedented sustained bombardment of missiles and rockets by all these adversaries if hostilities break out.

In August, outgoing Home Front Minister Matan Vilnai, a former army general who was once deputy chief of staff, warned that threatened Israeli pre-emptive strikes against Iran's nuclear program could trigger a war in which the Jewish state would be hammered by hundreds of missiles a day.

This multi-front bombardment, lasting up to 30 days, would likely cause as many as 500 fatalities. Other projections put the toll far higher.

The U.S. administration of President Barack Obama has slated budgetary cutbacks totaling $1 billion over the next nine years, with around half of that coming from defense spending that includes funding for Israeli weapons programs.

In 2010, the United States provided some $205 million in fiscal 2011 for Iron Dome, designed to shoot down short-range rockets such as the Soviet-designed Grads and Katyushas widely used by Hezbollah and Hamas.

But only four batteries are in service in Israel. Israeli strategists say as many as 20 are needed to provide nationwide protection and much of the U.S. funding for the project is intended for procurement.

In May, the U.S. Congress approved nearly $1 billion for fiscal 2013, which began this month, for Iron Dome, along with the high-altitude, long-range Arrow-3 system, upgrading the existing Arrow-2 system currently deployed, and the David's Sling system still under development by Rafael and the U.S. Raytheon Co.

It's intended to intercept missiles with a range of 70-200 miles. State-owned Israel Aerospace Industries and Boeing of the United States developed the Arrow systems, which will form the top two layers of the planned defense shield.

Of the $948 million appropriation, Iron Dome was to receive $680 million, a substantial increase over the 2011 funding that underlined the urgent need for protection against salvos of short-range projectiles whose range is increasing all the time. That's enough to buy five or six more batteries.

David's Sling, known as the Short Range Ballistic Missile Defense program, was down to get an allocation of $149.6 million.

Arrow-3, lighter and more destructive than Arrow-2 and capable of intercepting ballistic missiles outside Earth's atmosphere, was due to get $74.6 million.

Another $44.3 million was to go to the Arrow System Improvement Program.

All of these appropriations were over and above the $3.1 billion military aid that Israel gets annually from the United States.

The Republicans currently control the House of Representatives, where the funding legislation originated. Democrats dominate the Senate and, despite some misgivings, have endorsed these appropriations to aid Israel's missile-defense shield.

U.S. firms envision exports of Arrow and other Israeli systems. Boeing, for instance, foresees global demand for Arrow-3, particularly with India, Singapore and South Korea.

Meantime, Israel's moving to integrate its air force and missile defenses to enhance protection against a major missile assault on the nation. This will include air, rocket and missile defense assets along with early warning, radar, passive defense and counter-strike capabilities.