Companies that make everything from soda cans to car hoods have been feeling the pain of more expensive aluminum due to higher U.S. tariffs and rising global prices. Now, the war in Iran is curtailing shipments of the metal from Persian Gulf producers, which supply about a fifth of U.S. imported aluminum.

The WSJ’s Bob Tita writes that a complex price system provides domestic buyers almost no protection from the U.S. tariffs on imported aluminum that have increased from 10% to 25%, and then to 50% since the start of President Trump’s second term. Although the Trump administration is preparing to overhaul its tariff scheme for steel and aluminum, the changes aren’t expected to affect imported commodity-grade metals.

Stocks of the metal in the U.S. are estimated at 200,000 metric tons, about two weeks’ worth of domestic consumption, compared with four to six weeks usually. Because of the high prices, metal traders and distributors have been reluctant to maintain larger aluminum inventories, company executives say. Meanwhile, domestic aluminum producers such as Pittsburgh’s Alcoa are benefitting from the higher prices.

The U.S. will insure losses up to $40 billion for tankers brave enough to transit the Strait of Hormuz—double its original guarantee announced a month ago, the Journal’s Jared Mitovich writes.

Berkshire Hathaway and Liberty Mutual are among six new insurers the federal government is teaming with to provide maritime reinsurance to ships traveling through the Persian Gulf. The U.S. International Development Finance Corp. is running the insurance program.

President Trump announced the reinsurance plan in early March, but the DFC has yet to launch a public application portal for insurance. The agency said it would soon share more information on the application process. Chubb will serve as lead underwriter and insure $20 billion of the losses along with the new partners. The DFC will insure the rest, Barron’s reports.

• President Trump threatened to destroy all of Iran’s power plants if the country’s leaders don’t agree to reopen the Strait of Hormuz by Tuesday evening. (WSJ)
• Authorities in the emirate of Sharjah said they were responding to an incident targeting Khor Fakkan Port, one of the UAE’s biggest container ports. No injuries were reported. (WSJ)
• Several Italian airports warned they are facing limited availability of jet fuel in the coming days. (WSJ)
• Iran’s military said Iraqi oil tankers were exempt from shipping restrictions in the Strait of Hormuz. (Bloomberg)
• A French-owned container ship, the CMA CGM Kribi, transited the strait, the first time a vessel with ties to Western Europe has been known to cross the channel since Iran began blocking it. (WSJ)
• CMA CGM secured Iranian assurances for safe passage of its 14 containerships stuck inside the strait since the war began, according to industry sources. (Journal of Commerce)
• Iran’s Revolutionary Guard Corps claimed to have struck a Mediterranean Shipping Co. containership with a drone in the strait. (TradeWinds)

Chinese companies are moving to cement their place in the supply chains for humanoid robots, the Journal’s Raffaele Huang writes. While the U.S. controls the best chips and other technology for robot brains, China holds an unrivaled grip on the manufacturing ecosystem for humanoids’ bodies.

Tesla is building a team in China to work with suppliers for its Optimus humanoid robot, and Tesla employees have visited Chinese makers of sensors, motors and other parts, people familiar with the project said. U.S. tech companies have long relied on manufacturers in China. But some U.S. policymakers are uneasy about how Chinese companies are taking a central role in the humanoid supply chain.

Beijing is treating the robot supply chain as an area of strategic importance, identifying embodied AI—the fusion of AI with physical systems—as one of six future industries expected to drive its economy.

• The U.S. added 178,000 jobs in March, the Labor Department said, the best month for job growth in more than a year and far surpassing February, when the U.S. lost jobs. Unemployment fell to 4.3%, from 4.4% in February. (WSJ)
• Trump released a 2027 budget proposal seeking $1.5 trillion for defense spending, the largest dollar amount in modern history, and cutting nondefense spending by 10%. (WSJ)
• China reserved swaths of offshore airspace without explanation for a period of 40 days, issuing alerts similar to those used to warn of military exercises. (WSJ)
• Thousands of striking JBS beef plant workers in Colorado agreed to return to work, ending a three-week strike. (WSJ)
• Microsoft plans to invest $10 billion in Japan over four years to develop AI infrastructure and strengthen cybersecurity. (WSJ)
• Chubb unit ACE American Insurance Co. reached a settlement with the owner and operator of the containership Dali, which allided with Baltimore’s Francis Scott Key Bridge two years ago. (Splash247)
• A.P. Moller-Maersk signed a lease for a 233,492-square-foot logistics center in Linden, N.J., to link warehouse and inland delivery networks. (NJBIZ)
• The U.S. Department of the Interior has begun an effort to consolidate regulation of offshore energy under a new Marine Minerals Administration. (gCaptain)
• Production of truck tires at Hankook Tire America’s plant in Clarksville, Tenn., is scheduled to begin in early July. (Transport Topics)
• Great Lakes shipyards operated by Fincantieri Marine Group are joining with Fraser Shipyards and Donjon Marine to compete for a contract to build Coast Guard light icebreakers. (WorkBoat)

Mark R. Long is editor of WSJ Logistics Report. Reach him at mark.long@wsj.com. Follow the WSJ Logistics Report team on LinkedIn: Mark R. Long, Liz Young and Paul Berger.