At 1:28 a.m. ET Tuesday, the 984-ft long container ship Dali crashed into the Francis Scott Key Bridge in Baltimore, bringing it down.

The ship had lost power and called in “mayday.” On-site officers can be heard holding traffic from the bridge in dispatch audio. The impact was captured on a livestream. A small construction crew had been fixing potholes on the bridge itself. Six are presumed dead.

The Port of Baltimore is now closed “until further notice,” halting some $15 million in daily economic activity. Cruise ships have been rerouted. The auto industry is facing supply chain concerns, with the port the top US handler for auto imports and exports.

There are environmental concerns. The ship carried 764 tons of hazardous material, and some containers have been breached.

And there’s a bill to pay. The ship’s owner is expected to invoke an 1851 law to limit its liabilities. A historic market in London will face billions in claims.

The crash was a tragic accident. It’s also what happens when 95,000 tons of modern cargo ship meets America’s aging infrastructure. And it’s a reminder of the precarity of just-in-time supply chains and global trade.