First, George W. Bush is not a king, and his signing an order exempting the Navy from compliance with environmental rules targeted directly at the Navy is awful. The order was related to using active sonar.
"An NRDC-led coalition of wildlife advocates succeeded in restricting the U.S. Navy's use of a powerful active sonar system known as SURTASS LFA in 2003." Here is a link to an little video clip, narrated by Pierce Brosnan no less, and an article by the NRDC.
I think protecting marine mammals is very important, even a moral obligation. The one thing that concerns me about the tone of the NRDC's fight, is the idea that nothing is lost by restricting the use of active SONAR. Active SONAR is an important tool in engaging the very quiet diesel electric submarines. Also, using sonar is much more difficult that one may think. For example, it is about a million times more difficult to use that RADAR. To be good at it, sailors have to train on it. And, there are limitations to simulators.
That said, the potential threat may be too slight to justify harming living sea creatures today. That is a worthy discussion.