Three years after the U.S. invasion of Iraq, what is most striking is the change in the way Americans discuss the war. Gone are measures of how many schools may be built, how much electricity is flowing and how soon the country’s oil will be able to pay for its reconstruction.

The bravery is still there and the constant effort, but those stories have been pushed off the front pages by bombings and assassinations, the grinding, daily tally of Iraqi deaths interspersed with reports of U.S. soldiers killed along with them. Now the overwhelming question is of another sort: When is it safe for the U.S. troops to depart?

That brings a less reliable measure of how well prepared Iraq is to carry out its own security. The answer: Not while Iraq stands on the brink of civil war, the mosque bombing in Samarra last month making even that precipice less certain, and not while the abilities of Iraqi security forces seem so modest.

On Thursday, when U.S. and Iraqi troops conducted helicopter and ground attacks on a suspected insurgent stronghold near Samarra, the House approved $67.6 billion to pay for military operations in Iraq and Afghanistan. That raises the total spent on the war and to fight terrorism since 9-11 to nearly $400 billion. But it is not the loss of treasure that most concerns Americans: More than 2,300 American soldiers have been killed in Iraq, some because they weren’t properly armored or equipped.

More than 200 soldiers from other countries have died there, too. There are no firm numbers on how many Iraqis have been killed, although President Bush has said 30,000 have likely died and other organizations put the number much higher.

There would be little point in reviewing, once again, the misinformation and mistaken perceptions of reality that led to a war very different from what the administration had described three years ago if not for the hope that some peaceful solution in Iraq may still be found – certainly, the willingness of Iran and the United States to talk about this is encouraging – and that the errors of pre-emptive wars will be avoided in the future.

President Bush a few days ago re-asserted this doctrine in the latest National Security Strategy, saying, “The fight must be taken to the enemy, to keep them on the run.” The enemy in Iraq ran, but not always in the direction anticipated.

The simplest threat to this policy remains: Any guess about what could happen in the future includes the possibility of being wrong, tragically so when considering war. The United States took its fight to its perception of an enemy in Iraq and found not security but surprise.

Three years later, it seems to be still discovering it.