Since 2011 Israel has operated one of the world’s most powerful and effective air defense systems that are designed to protect the inhabitants of the country from rocket and artillery attacks. The system is highly advanced and is comprised of mobile launchers, that work together to form batteries. Each battery is capable of protecting an urban area up 93 miles (150 square kilometers) in size. The system is called the Iron Dome, and so far it has destroyed between 80 – 90% of its targets.
Iron Dome

The idea of an Israeli missile defense system was first floated around in the 1990s, when Hezbollah, a political party and militant group, launched rocket attacks against urban areas in Israel. However, the idea was shelved at the time as it was deemed unrealistic.
In the mid-2000s the idea resurfaced and gained political support. Hezbollah fired more rockets into Israel in 2006, with approximately 4,000 landing in the country, killing 44 people and prompting the evacuation of hundreds of thousands of civilians.
In addition to this, approximately 8,000 rockets were fired into southern Israel from Gaza between 2000 and 2008.
In response to this constant and vast quantity of rocket attacks, Israel chose to construct the Iron Dome defense system. Rafael Advanced Defense Systems worked with the Israeli Defense Force to develop the shield, which cost $210 million. Just four years later, the Iron Dome was operational; a development speed rarely seen in the industry.
Not only was the Iron Dome quick to reach operational status, but it rapidly proved its effectiveness.
How does it work?

The Iron Dome is a system made of three main parts. The Detection & Tracking Radar detects the launch of the projectile and follows its trajectory as it passes into Israeli territory.
The Battle Management & Weapon Control then uses this information to calculate where it will land and decide whether this is a threat or if it will land harmlessly into unpopulated areas. If the rocket’s predicted impact location threatens Israeli civilians or other designated areas, the system will launch an interceptor missile.
The interceptor missile is launched from the Missile Firing Unit and will attempt to destroy the incoming rocket in mid-air, eliminating the threat.
Costs
The system works extremely well but is also extremely expensive to operate. The cost of each interception is estimated to be between $100,000 to $150,000. The huge expenses involved were criticized before the Iron Dome was even operational, with some arguing that the system costs a disproportionate amount of money destroying cheap missiles fired at the country. For example, a Qassam rocket only costs about $800.
Many in support of the Iron Dome believed these costs were more than justified by the lives it would save. Also, the cost of repairing damages caused by rocket attacks would likely be far greater than the cost of the Iron Dome.
The US has invested $429 million into the Iron Dome, while Israel has pledged $1 billion in funding to maintain the system in the coming years.
Disadvantages

There is no doubt that the Iron Dome works well and has certainly saved many lives but it is not impervious to all attacks. The system is vulnerable to high numbers of incoming rockets, which, in enough quantities, would overwhelm the Iron Dome and outnumber the interceptor missiles. In addition, low flying, short-range attacks are difficult to intercept.
Because of these physical limitations, Israel is investigating the possibility of complementing the Iron Dome with energy weapons that do not suffer from the same drawbacks and could supplement the interceptor missiles.
Some believe the Iron Dome has created additional political issues too. Because it is so effective, Israeli leaders may become too comfortable with their invulnerability, which removes the motive to make peace with their enemies.
“Iron Dome has altered the calculus of Israel’s political echelons in ways they have yet to understand,” a former Israeli official said. “It allows Israel to resist internal public and military pressure for a quick end to the conflict, and keep bombing Gaza.”