Sure, fire-fighters are typically courageous to do what they do--but theirs is not moral courage--which is what would be required to oppose official rules to aid peaceful protesters defend themselves against a brutal police.

  Generally, all a fire-figher needs is physical courage.  His moral courage might be a disaster and he could still do very admirable work fighting fires.

"In such an environment it is not surprising that the ills of technology should seem curable only through the application of more technology..." John W Aldridge