From a public relations perspective, Carnival Corp. may be doing the right thing by offering to reimburse the federal government for U.S. Navy and Coast Guard assistance that was rendered when ships were disabled.
But it sets a very bad precedent that the company was goaded into this voluntary payment by one powerful politician with an ax to grind, Sen. Jay Rockefeller (D-W. Va.). He may be a legislator, but this isn't what we mean by "the rule of law."
If the U.S. is going to have a system whereby the beneficiaries of these services are required to make a payment, then let's set up a system. What just happened is an example of what can happen when you don't have a system.