TO be honest, I was astonished that Tony Blair, the Met and the gang at MI6 failed to unleash a terrorism scare in the run up to last week's General Election.

Doorstep polling before May 5 showed voters firmly believed the Prime Minister's most valuable asset was his unshakeable decisiveness in a security crisis.

On that basis, I reckoned only a fool would bet against No 10 (c/o A Campbell) indulging in a spot of scare-mongering by flamming up a threat from barbaric extremists to our lives and liberties.

After all, we have had tanks deployed at Heathrow for no apparent reason and stories leaked from "well-placed sources" of thwarted chemical attacks on the Tube.

Muslims suspected of being involved in terror plots have been arrested in a blaze of publicity, grilled by police and hauled before the courts.

Mr Blair, you see, appreciates this truism: a perturbed public is a pliable public.

So a pre-poll warning from Osama Bin Laden, along the lines of the one delivered to the American public in - hold on to your hats, conspiracy theorists - the week before George W Bush won a knife-edge presidential election, would not have been totally unexpected.

But nothing came. An ashen-faced Tony Blair never appeared on TV to explain that, while the intelligence was "sketchy", an attack on our freedoms was a case of "when, not if", and that only a Labour government could mitigate against such an atrocity.

How come?

Firstly, the public's faith in Blair's grasp on intelligence in the wake of Iraq and the row over weapons of mass destruction is fragile as china.

Secondly, the trial of nine men accused of plotting to murder thousands of innocent people using deadly Ricin collapsed humiliatingly a fortnight before the election.

The jury, it seems, concluded the intelligence used to construct the case wasn't as reliable as the security services led us to believe.

It was surprising, then, to hear Alan Milburn, Labour's election campaign supremo, insist the Government planned to press ahead with controversial ID cards.

He said information revealed in the trial made it "clearer than ever that no serious party should play politics on terrorism."

The Identity Cards Bill should, therefore, be revived in Tuesday's Queen's Speech.

A storm looms. Ministers insist ID cards are crucial to the fight against terrorism, illegal immigration, people smuggling, and crime.

Critics claim they are an expensive attack on civil liberties.

However, rather than merely being a contentious piece of Government legislation, the Bill will be seen as a key test of how much power Mr Blair actually wields.

In the last Parliament, the Bill received its second reading - with the Conservatives abstaining, the Lib Dems opposed, and 19 Labour backbenchers rebelling. But it had to be dropped when the election was called.

But things are different two months on. Labour's majority has slumped from 161 to 67.

It is a strong, eminently workable majority.

But if the Tories and Lib Dems oppose the Bill, and Labour's 'awkward squad' of MPs join them - it would need just 34 rebels - the Bill would crash.

This would be hugely embarrassing for the Prime Minister, especially when he is facing mounting calls from his troops - including ex-Cabinet ministers - to quit sooner rather than later.

A defeat on ID cards would give fresh impetus to those who believe he has become a "lame duck" leader. His position would weaken. Leader-in-waiting Gordon Brown's would be stronger.

The Bill could be make-or-break for Blair's premiership. It will determine whether he still has the ability to persuade wavering backbenchers to back him over controversial legislation, or whether he will be forced to compromise.

He could drop the potentially problematic Bill altogether.

But this would also add fuel to accusations he has become so badly weakened he knows he cannot get ID cards through the Commons.

And if he finds himself in a hole over the legislation, it's not completely implausible to imagine Mr Blair dusting down a book entitled 100 Handy Terrorism Scares...

Updated: 11:09 Friday, May 13, 2005