Before they heard four U.S. special operations troops had been killed in a firefight against Islamic terrorists in Niger on Oct. 4, most Americans probably did not know our country had armed forces in that country.

But we have had troops there for many years. The total now is about 800, who are part of a French-led force battling Islamic militants in several West African nations.

Calls for more information about what went wrong on the mission that claimed the four Americans’ lives are being heard. That is entirely proper. Initial reports were that the U.S. troops were accompanying Niger forces on a fairly routine mission.

It turned deadly. Whether U.S. intelligence agencies should have learned of terrorist plans to ambush the joint force is a question.

So is whether air support could have arrived more quickly.

Unfortunately, however, the tragedy is a reminder of the deadliness of the foe we fight, as well as its widespread nature.

If the campaign against Islamic terrorists is not pursued aggressively, there’s no end to the amount of blood spilled.