Drawing the political lessons from by-election results is a tricky business - but it's now clear that a bad day for Labour ran so much deeper than just a little local difficult here in Brighton and Hove.
Haemorrhaging votes in the Goldsmid area of Hove will trigger political shock waves across the city - but its wider geographical impact will be limited.
Not so, perhaps, the result of the by-election in Norwich North sparked by a Labour resignation during the MPs' expenses scandal (remember that?).
The result, in a city not entirely dis-similar to Brighton and Hove, saw the Tories take the seat from Labour with a majority of about 7,000.
This is all bound to cause something of a crisis for the Labour Party - but no-one'll have the appetite for another leadership challenge, and clearly Gordon's not in the business of resigning.
But it shows how Labour are no longer capable of beating the Conservatives in parliamentary elections - regardless of who has held the seat previously, or by how big a majority.
The lessons, from both Norwich North and Goldsmid, seem pretty clear to me.
Both here in Brighton, and nationally, Labour are a spent force. Chances are we'll end up with a Conservative Government next year - and that'll be a disaster, for fairness, tackling poverty and deprivation, protecting the environment - and not least for the NHS.
But they won't win in a 1997-style swing to a charismatic leader and a whole new way of doing business - it'll be a victory by default.
And therefore all of us who want to protect public services and work for a fairer society should think about how to ensure the next parliament contains as diverse a group of opposition policies and ideas as possible - and here in Brighton that means returning Green MPs.
It's here we'll make the breakthrough of getting the first Green MPs elected. Challenging the Tories and working for both a fairer Brighton and more sustainable world is just too important a job to leave to the now fatally-wounded Labour Party.