The deal negotiated with Iran is worth the effort because it provides a chance to test whether the leaders of that nation's theocracy are serious about abandoning their nuclear weapons ambitions or are just stalling.

Neither side gave up much. Iran maintains the infrastructure necessary to develop a nuclear weapon. It did agree, however, to dilute its existing stock of weapons-grade uranium, place a cap on its stockpile of enriched uranium, and constrain installation of more centrifuges.

Combined with a plan for verification of these requirements, the deal at least lengthens the time it would take Iran's scientists to make a dash for development of nuclear warheads, giving the United States and its allies time to respond.

For their part, the United States and others involved in the multilateral talks - Britain, Russia, China, France and Germany - agreed to provide Iran access to $4.2 billion frozen in foreign banks, but the sanctions blocking international purchases of Iranian oil and the core of the banking sanctions remain in place.

The deal does not lift sanctions, as critics claim.

Arguably, a better deal would have Iran agreeing to eliminate centrifuges, shut down its underground enrichment plant and abandon or convert its heavy-water reactor in Arak, which will have the potential to produce plutonium for weapons. In return, of course, the international community would have needed to agree to lift all sanctions.

After decades of mistrust, neither side was prepared to go there. It was diplomatically unrealistic to think that all sides could reach such a comprehensive agreement in the first go around. It was an impressive diplomatic accomplishment for Secretary of State John Kerry to achieve this first step.

It should become apparent in the coming months if that first step is the only step possible. If inspectors find Iran violating the terms of this deal, the world needs to walk away and ratchet up the sanctions. Ultimately, the military option would come into play absent a comprehensive pact.

More likely, and more diplomatically difficult to deal with, would be Iran playing for time, offering small concessions in return for the lifting of more sanctions. Then, once economically stable, Iran's clerics could find excuses to abandon any agreements and go ahead full throttle with its nuclear weapons program.

The Obama administration and the international community cannot allow that scenario. Only a final deal that requires Iran to demonstrate the dismantling of its weapon-production infrastructure should be justification for lifting the core economic sanctions. Iran is unlikely to make such a final deal, but it is worth testing the regime, and this "Joint Plan of Action" provides that opportunity.

Israeli condemnation is understandable and of no surprise. Israeli Prime Minister Benjamin Netanyahu views the Geneva pact as evidence that President Obama is reluctant to exercise the military option and, as a result, will continue to dabble with negotiations that in the end will only provide the cover Iran seeks to race to a bomb.

President Obama's caution about an Iran attack is well founded, his decision to attempt diplomacy warranted. As noted here before, a military attack on Iran's nuclear-development installations would delay but not necessarily stop the program. Such an attack would likely have far-reaching consequences, potentially including anti-American revolts that destabilize other Arab nations, an Iranian military response targeting neighbors, disruption of global oil supplies and a damaged global economy.

In the end, such an attack may prove unavoidable, but it is worth a few months of talks to explore a peaceful option.