The men and women of the U.S. military and intelligence services are the most important part of America’s defense capital. When they enter the service of their choice they are well aware of the implicit contract between the nation and themselves. In return for their career, America has the right to call on them to go into harm’s way, very often at the risk of their lives. I have never known a Marine, a soldier or a CIA officer who did not accept this reality, and I have never known one who balked when called on to deploy. That said, each I have known — and I suppose all — hope that if defending America costs his or her life, the cause for which it is spent is clear and worthwhile. It is precisely on this point that the U.S. government’s executive and legislative branches are lethally failing these men and women.

The events of the past three weeks throw into sharp relief that we are sending our young men and women overseas to fight an enemy that does not exist. Among the first thoughts expressed by President Obama after the near-miss al Qaeda attack on Christmas — and then echoed by his lieutenants, various members of both parties in Congress, and numerous pundits — was that the young Nigerian bomber hated our way of life. And since seven CIA officers in Afghanistan were killed by al Qaeda on Dec. 30, the same thought has been expressed by the same people.

This central thought has been accompanied by additional assertions, among which are the attackers were nihilistic Muslim fanatics and the attackers’ motivation has nothing to do with Islam. The sum and substance of the U.S. bipartisan political elite’s response to recent events has been — as it has been since 1996 when Osama bin Laden declared war on America — that the Islamist terrorists hate us for who we are and how we live, not for what we do.

This contention is a fantasy. It is fair to say that all the U.S. Marines, soldiers and CIA officers who have died in Afghanistan since 9/11 and in Iraq since Saddam’s removal have died fighting an enemy that does not exist. In numbers now approaching 6,000, these men and women have bravely fought and died in combat against an enemy whose main motivation U.S. political leaders have consistently denied. No U.S. soldier, Marine, or CIA officer has been killed by an Islamist fighter who took the field because America has women in the workplace, beer is available in ample supply, and there are early presidential primaries in Iowa every fourth year. Indeed, Islamists motivated by such issues would not rise to the level of a lethal nuisance; they certainly could not stymie the U.S. military in Iraq and Afghanistan.

The young Nigerian in Detroit and the Jordanian bomber in Khost and his wife have told America’s Marines, soldiers, and CIA officers what they already surely sense, but what their political leaders deny. Both attackers cited motivations that pivot on U.S. support for Israel against the Palestinians; U.S. occupation of Muslim lands; and U.S. attacks on their fellow Muslims. The three individuals’ words echo the components of U.S. foreign policy named by bin Laden in 1996 as the causes of war — which also include U.S. support for Arab tyrants and exploitation of Muslim energy resources — and which polls show 80 percent of the world’s Muslims identify as attacks on their faith.

While it is hard for Americans to hear, we are at war with a steadily growing number of young men and women in the Muslim world because of what the U.S. government has done in that arena since 1945. The current slate of U.S. foreign policies toward the Islamic world generates the basic and most compelling and uniting motivation for our Islamist enemies.

Should some of these policies be changed? I surely think so, but that is a discussion for another time and broad public debate, perhaps during the 2010 midterm elections. For now, the discussion must focus on our enemies’ motivation and the knowing failure of U.S. leaders in both parties to be honest with our fighting forces. If we fail to understand that motivation, America cannot shape a war-fighting strategy to either defend those policies or defeat the tenacious, talented, religiously motivated, and growing foe our soldiers, Marines, and CIA officers are now losing to in the field. Those men and women — and their parents, spouses and children — deserve to know they are risking their lives to defeat a skilled and enduring enemy, one who is motivated by the impact of U.S. policies, and one that genuinely threatens America. They are not fighting the cartoon-like foe described by their political leaders for the past 15 years.