The Israel-Iran ceasefire held into its second day Wednesday, although concerns are swirling that the government in Tehran — if allowed to survive with even a small piece of its nuclear program intact — may now feel compelled to race toward a nuclear weapon as fast as possible.

The roughly 10-day Israeli air campaign and Saturday’s U.S. strikes on three key Iranian nuclear sites have, by all accounts, caused significant damage to Tehran’s nuclear program. Still, Iran possesses enriched uranium, and assessments from arms control organizations say multiple Iranian nuclear-related facilities may be viable.

Other Middle East powers are recalibrating their responses to the region’s fast-evolving geopolitics. Despite its criticism of Israel, Turkey could act as a bridge between adversaries. Omer Ozkizılcık, a security analyst in Ankara, says Ankara is engaged in backchannel diplomacy, with Turkish President Recep Tayyip Erdogan having persuaded Mr. Trump to consider direct talks with Tehran.

The unprecedented long-range bombing strikes by the U.S. on Iran’s nuclear plants, including sending decoy B-2 bombers to Guam, had the secondary impact of bolstering deterrence against a Chinese attack on Taiwan.

The bomber decoys fooled the Iranians and also served as a “brilliant deterrence operation,” according to Miles Yu, director of the China Center at the Hudson Institute and a former State Department policy planner on China. Mr. Yu, a contributor to Threat Status, says the mission sent a warning to China that it faces similar bombing strikes if President Xi Jinping orders his forces to attack Taiwan.

Mr. Xi has ordered the People’s Liberation Army to be ready for a military takeover of Taiwan by 2027. Mr. Yu says the U.S. operation against Iran will go down in history as a textbook example of operational planning and execution, perhaps the best since Napoleon’s tactical masterpiece in his 1805 victory at the Battle of Austerlitz in central Europe.

Japan’s military forces have conducted their first-ever missile test on Japanese territory, announcing this week that the Type 88 surface-to-ship, short-range missile was successfully fired at a training area on the nation’s northernmost island of Hokkaido.

The test on Tuesday marked a significant inflection point for Japan, which historically has avoided military shows of force under its pacifist constitution, but has been engaged in a major defense buildup in recent years amid expanding Chinese military muscle flexing in the region.

Tokyo adopted a five-year security strategy in 2022 that named China as Japan’s biggest strategic challenge and called for a closer military alliance with the United States. The Associated Press reported that Tuesday’s test featured a truck-mounted Type 88 guided missile, developed by Japan’s Mitsubishi Heavy Industries, with a range of about 62 miles.

North Korea “continues to produce fissile material — plutonium and enriched uranium — for nuclear weapons while enhancing its ballistic missile capabilities with a Hwasong-18, a solid fuel intercontinental ballistic missile capable of targeting the whole of the U.S.,” writes Joseph R. DeTrani, a former special envoy for the six-party talks with North Korea and director of the National Counterproliferation Center.

“Most recently,” he writes, North Korean dictator Kim Jong-un “talked about North Korea’s goal of having a blue water navy, which would give North Korea considerable reach in international waters. That would be an obvious threat to Japan and other neighboring countries.

“North Korea’s enhanced nuclear and missile programs, its mutual defense treaty with Russia — with more than 11,000 North Korean troops in Russia for the war with Ukraine — and its ballistic missiles and artillery and rocket launchers all require immediate attention.”

Clifford D. May examines Mr. Trump’s decision to strike Iran’s nuclear facilities, writing that the president “may have contemplated the risks of inaction” and weighed the question of “what would be required, over the decades ahead, to contain a nuclear-armed regime committed to jihad and increasingly allied with the anti-American dictators in Beijing, Moscow and Pyongyang.”

“Viewed in this light, defanging [Ayatollah Ali] Khamenei is unmistakably an ‘America First’ and Make America Great Again policy,” writes Mr. May, who asserts that, “had Mr. Trump decided not to act, I’m convinced the Israelis had a plan to at least degrade Fordo. Such a plan would likely have been high risk, and it probably wouldn’t have set back Tehran’s nuclear program for very long.

“On Monday night, Mr. Trump announced a ceasefire. Maybe it will hold, maybe not. Even if it does, expect Mr. Khamenei to attempt to — you should excuse the expression — build back better,” writes Mr. May, founder and president of the Foundation for the Defense of Democracies and a Threat Status contributor. “If so, the U.S. and Israel have the means to bomb back better. Their leaders have demonstrated that they also have the will.”

• June 25 — Algorithms and Authoritarians Hearing, House Select Committee on the Chinese Communist Party 

• June 26 — The Future of NATO Defense, Resilience and Allied Innovation, Center for Strategic & International Studies

• June 26 — The Realities of an Invasion of Taiwan, Stimson Center

• June 30 — Bolstering the Transatlantic Partnership at a Global Inflection Point, Atlantic Council

• July 13-17 — GenAI Summit, GenAI Week

• July 15-18 — Aspen Security Forum, Aspen Institute