Regarding Iran, a clock — but so far, not a nuclear bomb — is ticking.

That's important context in the conflict between Tehran and Washington. Iran has never developed a nuclear weapon, and a dash to deployment is not imminent. Still, it's wrong that Iran is elevating its uranium-enrichment level to 4.5%, which is above the limit allowed in the 2015 nuclear deal between Iran, the U.S., U.K., France, Germany, China and Russia.

And it's not the only barrier broken by Iran: The 300-kilogram limit on low-enriched uranium has also been surpassed.

There will likely be more incremental violations as Iran tries to pressure those nations adhering to the pact to end the strict sanctions the Trump administration imposed after the U.S. unilaterally pulled out of the deal.

Those sanctions were for a legitimate purpose: Curtailing Iran's malign activity throughout the region. But while the economic punishment has crippled Iran's economy, it has also crimped Washington into a difficult diplomatic position with allies adhering to the agreement, as well as with Russia and China, which used unusually blunt language to criticize the United States.

"It has been proven that unilateral bullying has become a worsening tumor and is creating more problems and greater crises on a global scale," Chinese Foreign Ministry spokesman Geng Shuang said on Monday. The ominous tone has implications beyond Iran: Chinese cooperation is essential to solve another dispute with a nation that actually has nuclear weapons: North Korea.

The agreement (officially the Joint Comprehensive Plan of Action, or JCPOA), was imperfect. But it offered the best method to diplomatically curtail any ambitions Tehran had on developing a nuclear-weapons program.

Now, although the Iranian violations of the deal are relatively minor, the risk is a dynamic where the government feels compelled to ratchet up its provocations to a level where it actually is closer to reducing the time it would take to proliferate, something the JCPOA was meant to avoid.

"I don't think the signal they're trying to send is, 'We're going all out to try and get nuclear weapons,' " Mark Bell, a University of Minnesota assistant professor of political science, told an editorial writer in an e-mail exchange. "I think Iran is trying to say, 'Here are some steps we can take, but there are a lot of other steps we could take if we wanted.' "

Bell, an expert on proliferation, added that "Iran has run out of patience and is now beginning to ramp up the pressure on the E.U. [European Union] and U.S. to try to persuade the U.S. to return to the JCPOA, have the Europeans compensate for the sanctions relief they have lost from the U.S., or negotiate a new deal. I would anticipate further steps in the future as Iran continues to increase the pressure."

An increase may in turn pressure the president, egged on by his hawkish secretary of state and national security adviser, toward a spiral that could trigger yet a bigger foreign policy catastrophe than the Iraq war — a military misadventure that Trump campaigned against.

Both sides are inching toward a war the world must stop: Time is working against a peaceful resolution of the dispute.

Accordingly, the time for more vigorous global diplomacy is now.