So perhaps the Cabinet minister quoted in Andrew Rawnsley's thought-provoking Observer column today is simply trying to take the edge off that moment, by suggesting they should expect to be around 5% in the polls a year from now.
"We're relying on you to find us the money," one of Mr Duncan Smith's ministers was told by a minister from another department. "Fine," replied the DWP Minister. "So long as you don't mind having a lynch mob outside your constituency office."
Yes, it has already got to the point where ministers are threatening each other with lynch mobs. One Lib Dem member of the cabinet recently gave me his private estimate of where the opinion polls will be in about a year's time. His forecast was: "25-5". By that, he meant the Tories will slump to 25% over the next 12 months and the Lib Dems will collapse to 5%. This was not a frivolous forecast, but a deadly serious one.
But who would make a deadly serious forecast like that?
Cue a Westminster village guessing game. There are five LibDems in the Cabinet - and it is a safe assumption that this isn't Nick Clegg speaking. Nor would I especially suspect his close confidant, Danny Alexander, who is in charge of the cuts, and it seems a little confident to think that Michael Moore would risk making waves with such a remark.
Many might think the prediction fits with Vince Cable's wise and sombre public persona but I would not personally place him top of my suspects list. For personally (and without any proof), I would like my fiver in a sweepstake on this matter to plump for the most likely culprit being Chris Huhne.
Huhne was once himself a Guardian and Independent journalist. And he sometimes appears capable of a healthy detachment when it comes to observing the party's electoral prospects under the man his leadership campaign once dubbed "Calamity Clegg". As circumstantial evidence for this unproven theory, I note that he has taken to publicly joking about the LibDem polling, with the amusing claim which could prove an effective tactic for settling party nerves that, back in the day, the LibDems were "just an asterisk" after their troubled merger. (Not quite true, though they did hit 3% in one 1989 poll. (Hat tip: David Boothroyd, and UK Polling Report).
As I say, just a hunch. We would naturally be only too happy to carry a response or denial from Huhne, and indeed from any or all of the other four too! Perhaps we will never know. Though I would not be surprised if most of the LibDem Cabinet Five end up, by the end of conference week, being asked in broadcast interviews whether that they take this view. Perhaps they may all have to deny it on the record, honestly in four cases, or one of them might even want to own up to it.
In the interest of equal opportunities, we could extend the guessing game to the Tories, the Rawnsley column includes this:
A senior Tory in the cabinet agrees with the Lib Dem leader that it is not comparable with the 1930s. This minister thinks the decade you have to go back to is actually the 1920s. There has not been a spending squeeze like it, remarks this minister with a sense of history, since "the Geddes Axe".
I would guess this is most likely to be Oliver Letwin - though perhaps David Willetts would be a possibility too. How many other Tory cabinet ministers could cite Lloyd George's ministerial team? (Though I imagine the Treasury Ministers will have been briefed on the historical comparisons).