The chief concern is that Pyongyang's defiance of the international community will serve as a case-study for how Iran also might side-step diplomacy, acquire nuclear weapons, and fuel a regional arms race. If North Korea can get away with becoming a nuclear nation with little punishment and despite US diplomatic efforts, Israeli analysts say that may embolden Iran to flout international pressure, too.
"If the Americans can't show credibility on North Korea, then they won't be able to go far. It's a thermometer," says Gerald Steinberg, a political science professor at Bar Ilan University. "The US has been threatening to take action against North Korea since the 1990s and the North Korea has been able to buy time. The Israeli concern is that's exactly what will happen with Iran."
Israeli experts believe that it should have been easier to apply a mix of diplomatic and military pressure on North Korea than Iran because of its comparative geographic, economic, and political isolation.
"This is open season for nukes," says Uzi Rubin, a former military Israeli intelligence officer who served as head of Israel's Missile Defense Organization from 1991-99. The North Korea test last week was a "watershed event. It means that even if you have minimal technology and are isolated, if you really concentrate on it, you can get nuclear technology."
Israel pushes for strong international response
Mr. Rubin adds that international diplomacy is useless if not backed up by a credible threat of force.
"Here we have a country [North Korea] that has reneged on all of its international commitements and gone nuclear against the advice of all the international community. Other countries considering to do the same will now be watching and drawing conclusions," says Yigal Palmor, a spokesman for the foreign ministry.
In the wake of North Korea's test last week, a foreign ministry statement called on the international community to "respond decisively ... so as to transmit an unambiguous message," Haaretz reported.
Addressing an Asian security conference in Singapore this weekend, US Defense Secretary Robert Gates said that the US would not tolerate a nuclear North Korea, and warned that if diplomacy failed, tougher measures would be considered.
"The United States and our allies are open to dialogue, but we will not bend to pressure or provocation," said Mr. Gates. "We will not stand idly by as North Korea builds the capability to wreak destruction on any target in Asia – or on us."
N. Korean ties to Iran
According to a technical report published earlier this month by Massachusetts Institute of Technology professor Theodore Postol, Iran's ballistic missile program "relies very heavily" on North Korean components, which it began importing as early as the 1980s. Three of its four known missile systems have flight characteristics "essentially identical" to those of North Korean missiles, the report says.
US intelligence officials believe North Korea and Syria, which have a longstanding military relationship, began cooperating on nuclear issues as early as 1997.
After Israel destroyed an alleged nuclear reactor in Syria in September 2007, the US accused North Korea of providing the nuclear know-how for the plant. Any transfer of technology from Pyongyang to Damascus is prohibited under United Nations Security Council Resolution 1718, which was adopted in response to North Korea's 2006 nuclear test.
Where the US, Israel go from here
Despite international consensus that Israel is a nuclear power, the country has never confirmed or denied its non-conventional abilities and has refused to sign the Non-Proliferation Treaty (NPT), which would require it open up its nuclear program to international inspectors.
North Korea withdrew from the NPT in 2003. That year, former president George W. Bush launched the Proliferation Security Initiative (PSI), an alliance of US allies to blockade and monitor transfer of non-conventional weapons between states.
The PSI is being mentioned as a possibility for stepping up pressure against North Korea, but Professor Steinberg was skeptical as to whether US allies in Europe would reach a consensus to apply it.
The degree to which the Obama administration succeeds or fails on North Korea will impact its ability to coax Israel to go along with its effort to engage Iran in political talks to abandon its nuclear program, says Steinberg. With Israel worried that Iran is about to make the jump to becoming a nuclear power, President Obama said that the US should be able to tell by the end of the year whether its diplomatic efforts are making headway.