Dockworkers on the East and Gulf coasts could go on strike again in less than two weeks if they don’t reach a contract agreement with ports and shippers. Talks are set to resume next week, according to Bloomberg. The main sticking point between the two sides? Automation.

It’s a growing part of port operations around the globe. But the International Longshoremen’s Association does not want ports to adopt technology that could eliminate jobs. 

Ports were built for loading and unloading cargo from ships in many kinds of containers. As Johns Hopkins University professor Tinglong Dai pointed out, it was up to humans to understand the nuances.

“We knew the differences between different shapes, different sizes of those boxes,” he said.

But for several decades now, shipping containers have come in standard sizes, meant to easily move among boats, trains and trucks, said Phil Evers, an associate professor of supply chain management at the University of Maryland.

“So the handling is pretty straightforward. The ships are pretty straightforward in terms of how they hold the containers. It’s very easy to automate that process,” he said.

That’s happening at some ports in the U.S., but especially in Europe, Asia and the Middle East, said Margaret Kidd, a professor of supply chain and logistics technology at the University of Houston. 

Go to the most automated ports in Europe, she said, and you don’t see people. “People are in the background. They’re in offices. They’re in safer locations to execute their work,” she said.

And robots are operating cranes to move containers. That can make ports safer for the humans who are still around, Kidd said, since they don’t have to be near heavy equipment.

But it’s not entirely clear that automation actually makes ports more productive or efficient. 

Phil Evers at the University of Maryland said that’s in part because the work that needs to be done doesn’t change.

“A crane can only operate so fast safely, whether there’s a human running it or whether it’s automated,” he said.

What automation can lower, he said, are labor costs. As in employing fewer workers, which is what the longshoremen’s union is worried about. 

Daniel Flaming, president of the Economic Roundtable, argues that human workers should stick around ports because despite those standard containers, glitches and anomalies are inevitable.

“Ships that are coming in through rough seas may have containers that aren’t as well aligned as they should be. There may be damaged containers,” he said.

And people, he said, are better than robots at catching and fixing those kinds of problems.