For two and a quarter years, media commentators have been predicting the imminent demise of the coalition. Left-leaning wishful thinkers have been waiting for the Liberal Democrats to realise the error of their compromising ways, while those on the right have counted the days till the third party demonstrated their unfitness to govern. Up till now, this torrent of weak, pejorative analysis from both sides has lacked any evidence. The incentive for both David Cameron and Nick Clegg to make the coalition last for the full five years has been self-evident from the start.
Now the sharks are circling again - and this time there is indisputably blood in the water. One side has indeed lost sight of the bigger goal and demonstrated its selfish lack of discipline.
No-one should be surprised that it was the Tories.
So, is the coalition now doomed? Have Cameron or Clegg's incentives changed? Far from it. Cameron is now in real trouble. His inability to make his backbenchers stick to the coalition agreement reveals a man utterly out of control of his party. In leadership terms, he ranks below Gordon Brown or John Major at the moment. Like that hapless pair, Cameron's only hope is to stick it out till his luck changes - unless the next election comes sooner.
As for Clegg, the Tory betrayal has presented an opportunity to change his destiny. All the opprobrium he has faced in the last two years boils down to one, devastating, charge: that he sacrificed his party's principles in the desire to smooth the path of coalition government. Now that the gloves are off, he must not miss the chance to change people's minds. His justified fury at Conservatives' stubborn defence of the indefensible has shown him to be a man of principle. Next, he has to establish that he will always put the pursuit of Liberal Democrat principle above an easy ride in cabinet. To do so, he must immediately up the ante. House of Lords reform is important - it attacks vested interest and over-concentration of power, as Liberals have always done. But it doesn't stir the blood in mid-recession. Now it is time to demand a Liberal approach to the economy: Keynesian stimulus, wealth taxes and more, not less, support for the most vulnerable. Of course, his Tory cabinet colleagues won't like it - but, frankly, they owe him. And pleasing them should never have been his main concern.
Can the coalition continue on that basis? Of course. Yes, it will be more difficult to agree each step - but that won't do this government any harm. It has so far been far too quick to rush policies out without thinking them through properly - the Health and Social Care Bill springs to mind. More robust scrutiny and debate will make that impossible, which will in turn demonstrate the value of coalition itself to voters. Two radically different parties exaggerating their similarities and keeping their disagreements out of sight has always looked phoney. Having the courage to debate different ideas publicly, then coming together to agree how best to get us out of our economic hole - that would look like mature government. Let's hope Cameron and Clegg are man enough to do it.
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