WASHINGTON - The conflict that ended, for now, in a cease-fire between Hamas and Israel seemed like the latest episode in a periodic showdown. But there was a second, strategic agenda unfolding, said U.S. and Israeli officials: The exchange was something of a practice run for any future armed confrontation with Iran, featuring improved rockets that can reach Jerusalem and new anti-missile systems to counter them.

It is Iran, of course, that most preoccupies Prime Minister Benjamin Netanyahu and President Obama. While disagreeing on tactics, both have made it clear that time is short -- probably measured in months -- to resolve the standoff over Iran's nuclear program.

One key to their war-gaming has been cutting off Iran's ability to slip next-generation missiles into the Gaza Strip or Lebanon, where they could be launched by Iran's surrogates, Hamas, Hezbollah and Islamic Jihad, during any crisis over sanctions or an Israeli strike on Iran's nuclear facilities. Michael Oren, the Israeli ambassador to the United States and a military historian, likened the insertion of Iranian missiles into Gaza to the Cuban missile crisis.

"In the Cuban missile crisis, the U.S. was not confronting Cuba, but rather the Soviet Union," Oren said. "In Operation Pillar of Defense [the name the Israel Defense Force gave the Gaza operation], Israel was not confronting Gaza, but Iran."

It is an imprecise analogy. What the Soviet Union was slipping into Cuba 50 years ago was a nuclear arsenal. In Gaza, the rockets and parts that came from Iran were conventional, and, as the Israelis learned, still have accuracy problems. But from one point of view, Israel was using the battle to learn the capabilities of Hamas and Islamic Jihad -- the group that has the closest ties to Iran -- as well as to disrupt those links.

Indeed, the first strike in the eight-day battle arguably took place nearly a month before the fighting began -- in Khartoum, Sudan, as another mysterious explosion in the shadow war with Iran. A factory said to be producing light arms blew up in spectacular fashion on Oct. 22, and within two days the Sudanese charged that it had been hit by four Israeli warplanes that easily penetrated the country's airspace. Israelis will not talk about it. But Israeli and U.S. officials maintain that Sudan has long been a prime transit point for smuggling Iranian Fajr rockets, the kind Hamas launched against Tel Aviv and Jerusalem over recent days.

The missile defense campaign that ensued over Israeli territory is being described as the most intense yet in real combat anywhere -- and as having the potential to change warfare in the same way that novel applications of air power in the Spanish Civil War shaped combat in the skies ever since.

Of course, a conflict with Iran, if a last ditch-effort to restart negotiations fails, would look starkly different than what has just occurred. Just weeks before the outbreak in Gaza, U.S., European and Persian Gulf Arab allies were practicing at sea, working on clearing mines that might be dropped in shipping lanes in the Strait of Hormuz.

But in the Israeli and U.S. contingency planning, Israel would face three tiers of threat in a conflict with Iran: the short-range missiles that have been lobbed in this campaign, medium-range rockets fielded by Hezbollah in Lebanon, and long-range missiles from Iran.

The last of those three could include the Shahab-3, the missile that Israeli and U.S. intelligence believe could someday be fitted with a nuclear weapon if Iran ever succeeded in developing one and -- the harder task -- shrinking it to fit a warhead.

A U.S. Army air defense officer said the U.S. and Israeli militaries were "absolutely learning a lot" from this campaign that may contribute to a more effective "integration of all those tiered systems."

The goal, and the challenge, is to link short-, medium- and long-range missile defense radar systems and interceptors against the different types of threats that may emerge. Even so, a historic battle of missile versus missile-defense has played out in the skies over Israel, with Israeli officials saying their Iron Dome system shot down 350 incoming rockets -- 88 percent of all targets assigned to the missile defense interceptors.

Before the conflict, Hamas was estimated to have amassed an arsenal of 10,000 to 12,000 rockets. Israeli officials say their pre-emptive strikes on Hamas depots reduced the arsenal of missiles -- both those provided by Iran and some built in Gaza on a Syrian design.

Israeli officials stress that most of the estimated 1,500 rockets fired by Hamas were on trajectories toward unpopulated areas. The tracking systems of Iron Dome are designed to discriminate between those hurtling toward a populated area and strays not worth expending a costly interceptor to knock down.

"This discrimination is a very important part of all missile defense systems," said the U.S. Army expert. "This clearly has been a validation of the Iron Dome system's capability."

Experts said that Iran also was certain to be studying the apparent inability of the rockets it supplied to Hamas to effectively strike targets in Israel, and could be expected to re-examine the design of that weapon for improvements.

Israel fields five Iron Dome missile defense batteries, each costing about $50 million, and wants to more than double the number of batteries. In the past two fiscal years, the United States has given about $275 million in aid to the program.

However, Iron Dome has its limits. It is designed to counter only short-range rockets -- those capable of reaching targets at a distance of no more than 50 miles. Israel is developing a medium-range missile defense system, called David's Sling, which was tested in computer simulations, and has fielded a long-range system called Arrow.