Mr Tony Blair has vowed that Britain and America will not falter or flinch, stop or fail in their assault on global terrorism.
Mr Blair was beginning a tour of the Middle East last night, becoming the first British Prime Minister to visit Syria.
Before departing he delivered a defiant speech to the Welsh National Assembly, citing "a flood" of fresh evidence linking Osama bin Laden to the Washington and New York atrocities as he again spelt out allied war aims and sought to stiffen British resolve amid the first signs of wavering public support for the continuing military action in Afghanistan.
Inside Afghanistan, he said, were "sworn enemies of everything the civilised world stands for" - who had already killed on a vast scale and would do so again unless stopped - and who had but one hope.
"That we are decadent, that we lack the moral fibre or will or courage to take them on; that we might begin but we won't finish; that we will start, then falter; that when the first setbacks occur we will lose our nerve," he said.
He declared: "They are wrong. We won't falter. We will not stop until our mission is complete. We will not flinch from doing what is necessary to complete it.
"We will not fail and we will do it all because we believe in our values of justice, tolerance and respect for all regardless of race, religion or creed, just as passionately as they believe in a fanatical hatred of Jews, Christians and any Muslims who don't share their perverse view of Islam."
Mr Blair struck a conciliatory note with critics of his government's support for the American-led war, insisting they were not appeasers or faint-hearts.
"We are a democracy, strong enough to have doubts raised even at a time of war and wise enough to be able to respond to them."
And having warned this would be "the testing time", Mr Blair understood that people wanted results as quickly as possible. "They realise the formidable challenges posed by any action in Afghanistan. They worry about civilian casualties. They are anxious about the refugee crisis as winter approaches. They wonder what comes after the conflict. All these concerns deserve to be answered. No-one who raises them is an appeaser or a faint-heart."
However, Mr Blair urged people not to forget the reasons for the military campaign. "If we do not act against al-Qaeda and the Taliban, al-Qaeda will have perpetrated this atrocity, the Taliban will have sheltered them, and we will have done nothing."
"We will have done nothing despite the fact, also inescapable, that they intend to commit more atrocities unless we yield to their demands which include the eradication of Israel, the killing of all Jews and the setting-up of fundamentalist states in all parts of the Arab and Muslim world."
Reiterating the aims of the coalition, Mr Blair continued: "Our objectives are clear: to close down the al-Qaeda network, bring Osama bin Laden and his associates to justice, and because the Taliban regime have chosen to side with al-Qaeda, to remove them."