My belief is that you cannot make a hard and fast rule. Generally you should keep promises; it's important to be dependable.

But:
If you break a promise you are responsible for breaking it.
If you do not break it you are responsible for keeping it.

Some years ago two drunken young men agreed that women were no dam good and they'd go home and kill their wives. The one that was married to a cousin of mine kept the agreement and stabbed her to death and left her in a field. The other one broke his oath & didn't kill his wife.

Well, the correct morality in that situation is a lot easier to see than in Claire Short's case. I don't know enough about that to have an opinion, but she has to make the same decision those boys had to: which is the lesser evil?

You cannot sign your conscience over to another person or to a rigid abstract principle. You have to look at it case by case.

clint