>Weren't these contractors already paid for the entire wall?
I don't know. What I do know is that they would be under contract before they'd move all that equipment and material while hiring hundreds of skilled workmen.
Biden can fuck with the money, but he is going to get the government sued for breach of contract. This article claims it will cost Billions.
https://www.borderreport.com/hot-topics/the-border-wall/terminating-border-wall-contracts-would-cost-billions-says-cbp-head-but-us-has-options/