NEW YORK — When an American spy satellite detected the launch of an Iranian medium-range missile last week, international attention focused immediately on Israel as a potential target of the Gulf state's expanding arsenal.

The missile — which is presumed to be based on a North Korean missile — has an estimated range of 800 miles, encompassing all of Israel, most of the Persian Gulf region and Turkey, and parts of Russia, Egypt and India.

But Middle East experts are cautioning against drawing conclusions about Iran's true military capability and its intention in testing the Shahab-3 missile.

"It's one thing to test, and another thing to have the capability," said Daniel Pipes, editor of the Middle East Quarterly. "Testing in and of itself is not the key."

Although the motivation behind Iran's testing is not clear, some analysts believe that it may have had more to do with internal Iranian politics or the desire to assert itself in the region than with targeting any particular nation.

Iran has said that the missile was intended for defensive purposes.

Since the Iraq-Iran War in the 1980s, Iran's possession of Scud missiles has been well-documented. Iran is also known to harbor and sponsor terrorists, who have struck in Egypt, Israel and Turkey.

The test represents a new level of weapons sophistication.

The missile may have been purchased from North Korea or it may have been reverse-engineered, indicating that Iran has a more advanced degree of technical expertise than was previously thought.

"A missile test does not operational capability make," said Michael Eisenstadt, a senior fellow at the Washington Institute for Near East Policy.

Full capability may be two years off, Eisenstadt said, assuming that Iran follows the same exhaustive testing protocols that America does.

Other strategic experts point out that India's missile program took twice that time to develop with far fewer restraints

The Iranian test may have come sooner than expected, but Iran's missile development program has been an "open secret" for some time, known to observers of the region as early as 1992. Since then, Iran reportedly has been working to develop its version of the Korean missile.

Over the past year and a half, Israel, a main target of official hostile propaganda from Iran, has voiced concerns over Russian firms providing technical involvement in the Iranian program, lobbying the United States to halt Russian assistance.

In a conference call to representatives of the Conference of Presidents of Major American Jewish Organizations, Israeli Prime Minister Benjamin Netanyahu — who has issued no official statement about the Iranian action — said that while Israel was still assessing the test to determine its immediate significance, it would now need to work on all of its defenses, according to sources on the call.

Experts agree that Israel will continue to develop Arrow anti-missile missiles, a program funded in part by the United States, and will further accelerate upgrades to its stock of Patriot missiles.

But there is no clear evidence of an increased threat to Israel, or even whether the Shahab would be used as a ballistic weapon.

"There is nothing automatic about this," said Richard Murphy, a senior fellow for the Middle East at the Council on Foreign Relations. He noted that Syria has for many years had mid-range missiles.

The test "was designed to impress, " said Murphy, a former U.S. assistant secretary of state for Near Eastern and South Asian affairs.

Medium-range missiles, because of their inaccurate trajectories, are ineffective for conventional weapons.

As a terror weapon, however, the missile could be outfitted with a chemical or biological warhead, experts say.

However, Leonard Cole, the author of "The Eleventh Plague: The Politics of Biological and Chemical Warfare," said such a use is unlikely.

In order to introduce chemical or biological weapons into a population, he said bluntly, "all you need to do is carry a vial of bacteria."

While many fear that Iran has nuclear ambitions, Yiftah Shapir, a researcher at the Tel Aviv University's Jaffee Center for Strategic Studies, said it has a different potential aim.

"I wouldn't be surprised if Iran were looking further to the future" about 20 years, he said, "looking forward to using these missiles for launching satellites" for potential spying or communications purposes.