Are they playing with us again? I mean, all that talk about terrorist threats so detailed that the government had to move quickly to raise the alert status to orange and to screw up traffic around the World Bank and the International Monetary Fund.

Is this prudence? Is it a domestic psy-war charade? Or is it an embattled incumbent reminding us that he is a "war president"?

Several things prompt these thoughts that, at some level, amount to an accusation I don't want to make. The first is the revelation in The Post early last week that the information on which the administration was acting was three years old -- based on surveillance conducted before Sept. 11, 2001. That doesn't make it untrue, of course, but doesn't it make it a little less reliable? It's not like the information was to the effect that al Qaeda would launch a strike against important international banking facilities in the Washington and New York areas the first or second week of August 2004.

But even if it had been that specific, wouldn't any reasonably smart terrorist, having seen his "secret" plans splashed across the front pages of all the top newspapers, change those plans? It isn't like scrambling fighter jets to intercept an already launched attacker. It's more like moving into a hotel for the night after learning -- and announcing the fact -- that an assassin had made plans to fire into your bedroom that evening.

If you were driving a truck loaded with explosives with which you intended to knock over the New York Stock Exchange, wouldn't reports of extra-tight (and temporary) security around the exchange lead you to delay your attack -- or to pick a different target?

My normal tendency is to avoid such second-guessing, on the assumption that my government (1) is well-intentioned and (2) knows more than I do. That predisposition has been harder to maintain since it has become clear that my government exaggerated the evidence on which it justified America's unilateral attack on Iraq. Sometimes, it now seems obvious, the government knows less than it tells you it knows. And sometimes its intentions are less than saintly.

Then there's this: The president, locked in a tight race for reelection, has discovered that he is most vulnerable on matters such as the economy and other domestic issues -- and strongest in the polls on matters directly related to national security and fighting terrorism. Would the guy who was willing to serve up "cooked" intelligence to justify an avoidable war be reluctant to head back to the kitchen if his job were on the line?

What makes this so difficult for me is that I don't know what a prudent president ought to do in the face of real, though less than specific, threats of terrorist attacks. I frequently hear from people whose judgment I value that if our government could have put together the bits and pieces of information it had, the Sept. 11 attacks might have been prevented.

I frankly don't see how -- short of shutting down civilian air travel and being prepared to shoot down commercial airliners. (By the time it became clear that American Airlines Flight 11 out of Boston had been hijacked and was headed toward New York, but before you knew the suicidal nature of the hijackers, would you have shot it down? Where?)

This anti-terrorism business is tough, fiendishly so when the enemy is clever, resourceful and patient. I wish our president the greatest success in combating it. We need it.

But we need something else. When our president tells us that our security is at risk, that attack is imminent -- when the shepherd boy tells us that the wolf is already among sheep -- we need to be able to believe him, without doubt or reservation.

As I recall Aesop's fable, the shepherd boy survived his mendacity, losing only his job. It was the sheep that took the hit.