In the wake of the Malaysia Airlines flight that's believed to have been brought down by a missile over Ukraine, and a Hamas rocket landing near Israel's main airport, Rep. Steve Israel is calling for all new U.S. passenger jets to be equipped with a missile defense system.

The New York Democrat told ABC News, "Terrorists are copycats, and I'm concerned that [when] they see these tactics, they're going to try and employ them. We know that there are thousands of shoulder-fired missiles in the hands of terrorists around the world. They're going to use these things and we are still leaving our public undefended."

Rep. Israel made a similar proposal after a 2002 missile attack on an Israeli charter plane flying over Kenya, but it didn't go anywhere.

Israel's El Al Airlines is reported to have anti-missile systems on its planes, which the congressman referred to in making his argument, saying, "If you're flying on an El Al aircraft, you're defended, Air Force One is defended, many military aircraft, defended. But no commercial plane in the United States fleet is defended. And that's just wrong."

Objections include the cost to airlines of installing the systems -- estimated at about $1 million per plane -- as well as that commercial pilots aren't necessarily trained on such equipment, and that defense systems would likely involve sudden maneuvers that commercial aircraft aren't designed to handle, which could endanger passengers.

This gives you an example of what a missile defense system looks like for an airliner:

http://youtu.be/PJGnDJ2l7mk