When the Chinese entered the Korean War in 1950, forcing a headlong American retreat, Gen. Douglas MacArthur told Washington, “We face an entirely new war.” The same can be said of Iraq’s first suicide bomber and the threat of many more to come.

This ominous new phase of the War in Iraq began a week ago when American soldiers were controlling a road into the besieged city of Najaf, a city in south-central Iraq, trying to halt a flow of enemy reinforcements from Baghdad. A taxicab drove up to the U.S. checkpoint. The driver waved for help. American soldiers approached. Suddenly the car exploded, and four of the Americans were killed. Iraq’s vice president, Taha Yassin Ramadan, promptly identified the suicide bomber as Ali Hamadi al-Namani, a noncommissioned army officer and father of several children, and promised more such attacks.

One immediate direct result was an incident at another nearby checkpoint. A civilian van approached. U.S. Army soldiers motioned for the vehicle to stop. The vehicle kept moving, and they fired into the passenger compartment. Then they found that the occupants were 13 women and children. Seven were dead and two others were wounded. The young soldiers, like the rest of the world, were shocked and horrified by the incident. But they believed they had been doing their duty. On Thursday, a suicide driver killed himself, his passenger – a terrified pregnant woman – and three coalition soldiers.

The coalition action, given the hopeful name “Iraqi Freedom,” has been billed as a liberation of the Iraqi people from a cruel and oppressive dictatorship. Civilians were expected to greet the invaders as their saviors. Some have done so, or have tried to do so, but necessary new security requirements make it difficult for civilians, even carrying white flags, to approach American solders. As one headline writer accurately put it, “Suicide assaults create wall around troops.”

Iraq’s No. 3 political leader may have been exaggerating when he claimed that “battalions” of Arab militants were arriving in Baghdad to join the fanatical paramilitaries known as fedayeen, or martyrs for God. He spoke of thousands of volunteer would-be martyrs from many Arab countries. But a New York Times dispatch from Damascus told of many volunteers, driven by religious zeal, Arab nationalism and outrage over the killing of Iraqi civilians, eager to catch a free bus ride into Iraq to give their lives to fight the “infidels.”

Thus, Saddam Hussein, a secular ruler often denounced by Osama bin Laden and other leaders of the Islamic terrorist network, seems to be trying to convert a U.S.-Iraq conflict into an American war against Islam and Arab nationalism. If his plan to expand suicide bombing succeeds, the United States will face a threat like the one that confronts Israel every day. This may lengthen the war; it certainly could make the peace far more difficult to organize.