Among the most loathed and dreaded phrases in the Imperial Military Service lexicon is this: “intervention outwith mission parameters is not required”.

That phrase is your lords and masters at CORECOM, usually prompted by advice from Admiralty Intelligence, ISS, the bright chaps at External Clarification & Rectification, or even the Conclave of Clionomy, telling you that your flag privilege to identify the right thing, the thing that the honor of Their Divine Majesties requires, and then do that thing has been – if not revoked – at least severely curtailed.

There’s a reason, of course. The supplementary data that comes with the mission orders tells you what future you’re buying with your restraint, with as many details as they can give you. You can override their call – but you need to be absolutely sure that you’ll win the trade-off, lest you spend the rest of your Navy career counting spacetight valves at the Depot logistics base.

If they need it revoked completely, they’ll escalate the euphemism to “we must stress: intervention outwith mission parameters is not required”. That’s politely mandatory, usually Fifth Directorate, and you don’t want to know the reasons they’re not telling you. In these operations, you don’t sleep well afterwards, but you’ll sleep less well for knowing the reason why.

Exceptionary Circumstances, those are called. Most officers will go through their careers without encountering any. Hope to be one of them, but be prepared for the worst.

– Fleet Admiral Ossil Teresu, classified memoir