As these industrialised countries, struggling with budget deficits and (in some cases) public war weariness chose to sit out foreign crises more often, the world seems to be becoming a less predictable and more volatile place.

BBC: UN Syria failure shows declining power of the West

The American public, showing real signs of war weariness after two ground wars over more than a decade, is unlikely to be enthusiastic about a military confrontation with Iran that is likely to be far more costly and indeterminate than either Iraq or Afghanistan.

CNN: What if Israel bombs Iran?

The Democrats owe their majority in large part to war-weariness.

ECONOMIST: The Democrats

The Republicans' crushing loss of both houses of Congress in the mid-term election of 2006, thanks in large part to war-weariness, crops up only in passing, as a possible impediment to the planned surge in Iraq.

ECONOMIST: More vice than virtue

More important, however, nationalists seem to have gained a political self-confidence that unionists now lack, born of both war-weariness and faith in the leadership of Sinn Fein and the moderate Social Democratic and Labour Party, the largest nationalist party.

ECONOMIST: Ulster waits

The question now is whether the political problems facing the American-led coalition ranging from impatience in America to war-weariness among allies, including sections of the British public, and disunity among the Afghans will pile up so fast as to cancel out any progress that the military campaign might be making.

ECONOMIST: The military campaign: Steadying nerves | The

But there is an overall weariness of war, and a growing acceptance that the Taleban, who promised to unify the country under their rule, have failed to do this.

BBC: Afghans