Iran continues to boast about its successful uranium processing while insisting it is using it solely for peaceful purposes, not nuclear weapons. Nobody really knows whether it is preparing for peaceful power or war making. United Nations inspectors have gone to Iran to try to find the answer.

Although President Obama and the Pentagon are speaking cautiously, 58 percent of a sample of Americans said the U.S. should use military force, if necessary, to prevent Iran from developing nuclear weapons, according to the Pew Research Center. Only 30 percent said the U.S. should not. This willingness to risk another major conflict comes despite the fact that two long and disastrous wars are only now winding down.

Iran, pinched by the tightening sanctions, now wants to resume the stalled six-nation talks aimed at resolving the situation. The objective would be a compromise. The Financial Times said rightly in an editorial that it has become essential to clarify “what level of Iranian nuclear capability the world can live with, subject to intrusive external monitoring to verify Tehran is not running a weapons program.”

Time online has reported a plausible diplomatic solution proposed by a former Iranian diplomat, Hossein Mousavian. He suggested that the Western powers recognize Iran’s right to develop nuclear technology, including the enrichment of uranium, and lift the current sanctions. Iran, for its part, would accept maximum transparency requirements under the Nuclear Non-Proliferation Treaty and accept limits on its enrichment levels and on the amount of low-enriched uranium it can stockpile. Mr. Mousavian suggested that other limits might be imposed on Iran’s nuclear activities during a “confidence-building period.”

Iran has signed the Non-Proliferation Treaty, which gives Iran and other signers the right to develop peaceful uses of atomic energy. Five countries — the U.S., Russia, China, Britain and France — are recognized as nuclear weapons states. Four other countries — India, Pakistan, North Korea and Israel — have acquired nuclear weapons or are presumed to have done so. None of the four is a party to the treaty. North Korea signed on but withdrew in 2003 and conducted announced nuclear tests in 2006 and 2009.

In this complex diplomatic and potentially military situation, Sens. Lindsey Graham. R-S.C., Joseph Lieberman, I-Conn., and Robert Casey, D-Penn., have introduced a bill for a resolution calling for a national policy of preventing Iran from not only acquiring nuclear weapons but even acquiring the capability to build them. It calls for Iran to agree to “the full and sustained suspension of all uranium enrichment-related and reprocessing activities.” The proposal has 35 co-sponsors of both parties, including both of Maine’s Republican Sens. Susan Collins and Olympia Snowe.

To get Democrats on board, Sen. Graham removed original saber-rattling language saying that it is within the power and capabilities of the United States government to prevent Iran from acquiring a nuclear weapons capability.

A complication, of course, is that the Non-Proliferation Treaty permits enriching uranium, a process that can lead to the development of both peaceful nuclear power and nuclear weapons.

As more and more countries are developing nuclear technology, some authorities oppose proliferation in any form, while others argue that the presence of nuclear arsenals assures a peaceful stand-off. The latter group cites the 40 years of cold war between the United States and the Soviet Union, when neither side used its nuclear weapons because it would have meant mutually assured destruction. A possible flaw in that “MAD” argument is that Iran has often supplied conventional weapons to terrorist groups and might do so with nukes. Terrorists, unlike nations, are often suicidal.

In an uneasy situation the eventual choice may be between an uncomfortable compromise and war, perhaps a long one.