As scientific detective work goes on to locate the terrorists responsible for the anthrax attacks, this latest threat makes it clear that we are in a war of fear versus fortitude. Whether those who murder by mail are connected to Osama bin Laden and Saddam Hussein or not, we now know that terrorism spawns more terrorism.

The cute words “copycat” and “band-wagoning” cannot obscure the reality that when ideologically driven institutions, such as Hitler’s Nazi Party and Stalin’s Soviet state, adopt terror as a matter of policy, deadly psychopaths of all stripes will take heart and join in.

The terrorism of the Taliban and al Qaeda, rooted in a version of Islamic ideology, will stimulate other deranged peoples to take their hideous plans off the shelf and put them into practice. In the aftermath of the Sept. 11 attacks came signs of stirrings among a variety of like-minded fringe groups: Maoists in India, anarchists in Germany, militias in America, and “loners” with twisted minds.

Fear is the fuel on which terrorism runs. The more fear their acts generate, the more terrorist attempts will be made, and by an ever widening circle of killers. There is no doubt that we can prevent the spread of terrorism so long as we refuse to be afraid, refuse to change our principles, or alter our common patterns of life and work. As Ralph Waldo Emerson said, “He has not learned the lesson of life who does not every day surmount a fear.”

Beyond this, America’s fortitude and increasingly credible commitment to carry on this war as long as necessary is showing positive effects not only on the Afghanistan front but elsewhere as well. In recent days the Irish Republican Army appears to have actually begun to give up its guns, finally realizing that its terrorist label is damaging its political position.

The Filipino government, encouraged by the United States, may be on the verge of effective action against Islamic terrorists in the southern islands, who have bombed, kidnapped and beheaded civilians and tourists for years. There are new hopes for Russian-Chechen peace talks. And Yasser Arafat has just appointed a representative for the Palestinian Authority in Jerusalem who is not only moderate but brave enough to speak openly about the need for Arabs to accept permanently the State of Israel.

Other regional conflicts where terrorists have been calling the shots are also showing brighter prospects for resolution than before the United States declared war on terrorism. This phenomenon might be called “collateral advantage.” Just as warfare inevitably brings the unwanted phenomenon of “collateral damage,” so a war resolutely fought, with convincing staying power, will bring wavering, frightened or reluctant leaders rallying to the counter-terrorist cause.

So on both sides of the ledger –blocking the bad and promoting the good –this is a war whose outcome will be determined by mental toughness. Realizing that fact is the first and most essential step toward victory.

Charles Hill is a diplomat-in-residence and lecturer in the Political Science Department.