For shipping, the spirit of US President Joe Biden's executive order on competition is as important as the letter.

The document, signed 9 July and raising the liner sector's hackles, does narrowly tailor the Federal Maritime Commission's (FMC) objective to investigating detention and demurrage charges levied on US exporters.

But the FMC is also the only federal agency to sign a memorandum of understanding with the Department of Justice's (DOJ) antitrust division and on Wednesday FMC chairman Daniel Maffei asked Congress for greater enforcement capacity.