The joint US-Israeli exercise dubbed Austere Challenge 2012 is not only a big, complicated and expensive joint drill.
It is a realisation that defending a nation against missiles is a task that cannot always be performed through the means of the country being attacked.
It is even more than that. It demonstrates the need for multi forces working together in order to provide an effective shield against the fast proliferation of rockets and missiles, not only in the hands of countries but also in the hands of terrorists.
The exercise that began earlier this week is the largest that has ever been performed jointly by the two countries.
It will test the best way to operate the locally developed anti rocket/missile systems such as Iron Dome and Arrow with US ones such as Aegis-class cruisers armed with anti-missile systems.
The exercise is the sixth in a series of large-scale missile defence exercises in recent years.
It involves some 3,500 US military personnel, 1,000 of them in Israel, and the rest with the US 6th Fleet in the Mediterranean or with the US Europe Command.
Some 1,000 Israeli troops are taking part, based in different locations in Israel.
This morning the exercise became very realistic as some 45 rockets were launched from the Gaza Strip into southern Israel. The Iron Dome intercepted the ones with a deadly trajectory.
This added a very realistic ingredient to the complex exercise. It emphasised that the threat is currently affecting Israel, but also that this situation may change very quickly.
Rockets and missiles are becoming the weapons of choice for many terror organisations, and joint operations such as the one being held in Israel could become necessary in other places.