Answering to terrorism as if it's an invasion from another country was a great mistake. To win, you need to understand the enemy.
Here's my translation of a text written by De Villepin (before the US elections):
Assimilating the struggle against terrorism to a mercyless war.
It supposes terrorism represents a clearly identified enemy against which a state can fight through combats ruled by principles. Terrorism gets rid of that definition: it doesn't represent a threat like the others , because it doesn't respect the rules of war; they don't wage war like us but massacre innocents.
There is no peace possible with terrorists, no agreement, no armistice, no truce.
Calling this a war against terrorism also gives a legitimacy and an audience they want. It valorizes their fight. It gives them a statute they seek in order to spread their extremist thesis. Al Qaeda wants and is recognized by the US. David against Goliath. It's the confirmation of a clash of civilization.
Facing the horror of terrorism, we might be tempted by exception laws, moving away from democracy , but it's a dead end. What would be a democracy worth if it didn't itself respect the values it tries to spread around the world? Wouldn't that mean terrorists have already won if not on the field but at least in our minds?
We all want to put an end to terrorist actions within the shortest delay. The use of force might be tempting. The whole difficulty is to combine the use of force with all the other means at our disposal to fight terrorism. The use of force alone will never help us overcome terrorism.
There's a power revolution: the most powerful military means are challenged by the smallest instruments. The inconsidered use of force can only reassemble and motivate groups which are dispersed. The use of aimed force is a delusion: the civil population always suffers no matter what technology is used. Martyrs are multiplying, which are
new icons for populations deprived of any perspective besides violence.

And Scott Ritter was right, right from the beginning.

Raoul