For anyone who remembers the last days of Thatcher, there seem to be a lot of similarities here.

• Thatcher looked impregnable and popular, except to others within her own party.


• There was a very loyal core of support, which kind of obscured how unpopular she'd become. Probably she didn't realize herself.
  
• She got unpopular, outside the party, because of something she forced the British people for ideological reasons, against their will : the poll tax.
  
• She got unpopular, inside the party because of a) a dictatorial style of premiership, and b) because a large part of the MPs in her party profoundly disagreed with her on another issue. (European integration)
  
• She left a legacy of infighting that wrecked the Tory party. Partly because she didn't promote talent so much as ideological faithful.
  

Well now. Is Iraq Blair's poll tax or his Europe? Ie. is it the thing which finishes his external popularity or his internal? I'm betting on "internal". When he does something that really pisses off the electorate, that'll be the end of him.

How the hell can Labour avoid the subsquent melt-down?

Possibly Gordon Brown is the answer here. As someone who can play both the "continuity with Blair success" card, and the "I'm really different and NOT Blair, and anyway we've always hated each other" card. He has a better chance than John Major. (Seen as ideological continuation, and then traitor)

Unless of course, whatever gets Blair chucked is Brown's fault.