Again, I'm not sure it's possible to elaborate rules that would apply in all circumstances. Essential to all of this is effective planning in the defence department. In a lot of cases, these things can be predicted. To the extent that things can be predicted, you can deal with surprises.
One of the criteria should be a surprise. Perhaps something happens on the cyber front, or we have a significant increase in Russian activity in th Arctic. Whatever the surprise, something that really takes the military and the government by surprise should be one criterion.
Also, I don't think we should ever send our military personnel into a war or a warlike zone unprepared and unequipped. I don't know to what extent it's true, but the example was given about our troops in Latvia not being equipped appropriately with helmets. I just don't get this. You cannot.... You should not send soldiers into a warlike zone without personal protective equipment. That would be one example, so it's when there's an immediate risk to the military as well.