Speaking as another ex-medic, Boab, I suggest that you should, first, remember that, while you may not "believe in war" or care about the fate of the world's oil companies, you certainly believe in caring for the wounded and sick. Iraq is going to be full of wounded and sick people, at least some of whom will be British soldiers just like you used to be.

On the practical level, you should find out what your legal obligations really are, and the true extent of your likely liability. If the coming excursion is anything like Gulf War I, by the time they get around to digging you out, the tumult and the shouting will be over and the captains and kings will be long gone. Plan your prevarications to the Personnel Selection Officer (or your bolt to Bolivia) when that OHMS letter is actually in your letter box.

When you have found out the facts (not your fears), you should talk the whole thing out with your fiancee and your employer. You may find you have less of a potential crisis on your hands than you think.