Here's why US Iron Dome is necessary, but will differ from Israel's

There are significant challenges to overcome if we are to deploy something similar to Israel’s acclaimed air defense network because the threat to America is quite different.

Robert Maginnis is a retired U.S. Army officer and the author of a dozen books, including the just-released "Preparing for World War III: A Global Conflict That Redefines Tomorrow."

Today, we face real threats such as nuclear-tipped intercontinental ballistic missiles (ICBM) launched from countries like China and Russia, which could put at risk the entire United States. During the Cold War (1948-1991) with the Soviet Union, we addressed that threat with our doctrine of "Mutual Assured Destruction." If Moscow attacked us with long-range nuclear missiles, we would retaliate with an overwhelming number of similar weapons that would result in the annihilation of both nations. That doctrine worked because it ratcheted up fear on both sides.