Sam is the host of the World Service.
Since the start of the Covid epidemic, cyber- attacks on one of the world's busiest ports have almost doubled.
According to Gene Seroka, the executive director of the Port of Los Angeles, there are 40 million attacks a month.
The busiest port in the western hemisphere is Los Angeles, which handles more than $250 billion of cargo each year.
Europe and Russia are thought to be behind the threats to the US economy.
The threats are coming from Russia. He told the World Service that they had to stay ahead of those who wanted to hurt international commerce.
Billions of dollars in goods are moved every year by the seaports.
The aim of the attacks is to cause as much disruption as possible and slow down the economy.
The Port of Los Angeles is working with the FBI to improve cyber-security.
One of the world's first Cyber Resilience Centres is part of the FBI.
Mr Seroka said that they need to take precautions against cyber-incidents that could threaten or disrupt the flow of cargo.
Increased protection against cyber-threats within the maritime supply chain is provided by the Cyber resilience centre.
It is a hub for the port to receive, analyse and share information with those who work on the dock.
Global supply chains slowed down as factories were closed and workers were not allowed to go to work.
The strain on supply chains has lessened. There were more than 100 container ships waiting to enter the Port of Los Angeles. There are many people waiting to dock.
Mr Seroka doesn't think the problem will be solved until at least the year 2023. He said there was not enough space for all the cargo.
The role that ports play in our nation's critical infrastructure has been proven over the past two years. We need to keep the systems as safe as possible.
The story can be heard on the World Business Report.