Tom Bowman

The recent crises in northern Africa, from Libya to Mali to Algeria, have raised a host of questions about the role of the American military command responsible for the entire continent.

Founded in 2007, the United States Africa Command, or AFRICOM, was created to train African militaries so U.S. troops would not be called upon in times of crisis.

An Army brigade from Fort Riley, Kan., some 4,000, soldiers, will begin helping to train African militaries. The idea is to help African troops beat back a growing terrorist threat posed by al-Qaida.

The American troops will head over in small teams over the course of the next year. The Dagger Brigade returned to Kansas last year from a deployment to Iraq, where it trained and advised that country's security forces.

Former Republican Sen. Chuck Hagel of Nebraska is said to be on President Obama's short list to be the next defense secretary. But even the possibility of his nomination has stirred up opposition — particularly from members of his own political party.

If Hagel can survive a political ambush in Washington, he would be the first Pentagon chief who saw combat as an enlisted soldier.

The blunt-spoken Hagel favors deeper cuts in military spending and is wary of entangling America in long overseas missions.

U.S. and allied officials say the forces of embattled Syrian President Bashar Assad have prepared several dozen bombs and shells loaded with the lethal chemical sarin.

The number is a larger estimate than has previously been reported. The Syrians loaded the weapons with the chemical agents in the past several weeks, the officials say.

Those preparations raise fears that the fighting against rebel forces could enter a new and more troubling phase, according to the officials, who requested anonymity.

Sailors, veterans and their families are saying goodbye in Norfolk, Va., on Saturday to the USS Enterprise, which was the largest ship in the world and the first nuclear-powered aircraft carrier when it was commissioned in 1961.

In its illustrious history, the Enterprise served at the center of international events for a half-century — from the Cuban missile crisis to Vietnam to the Iraq War.

And it had a distinguished Hollywood career as well, playing a leading role in the 1986 film Top Gun, which starred Tom Cruise as a young naval aviator.

Once a mob began attacking the U.S. Consulate in Benghazi, Libya, on the night of Sept. 11, officials in Washington, D.C., watched with alarm. Now, new details are emerging about their response to the deadly attack.

President Obama and his entire national security team monitored what was going on half a world away. Army Gen. Carter Ham, who was the regional commander for Africa, happened to be in Washington that day.

America's exit strategy in Afghanistan is to have Afghan forces take the lead in fighting for their country. But too often these days, the job still falls to U.S. troops.

A senior officer in Afghanistan tells NPR that Americans continue to coddle Afghan forces and that this must stop. Tough love is in, the officer says. He says the Afghan forces are far more capable than the U.S. estimates and have simply grown accustomed to the U.S. doing everything for them.

That pretty much sums up the situation in southern Afghanistan earlier this year.

President Obama said during Monday night's debate that the U.S. Army has fewer horses and bayonets than in the past.

That's true. Although Army Special Forces were on horseback in Afghanistan when they helped defeat the Taliban in 2001, the Army's horses are now used only for ceremonial occasions.

As for bayonets? The last bayonet charge was during the Korean War in 1951.

The bayonet has somewhat gone the way of the horse cavalry, as far as the Army is concerned (although Marines still use bayonets in training).

The second of two female Marines who tried to make it through the grueling Infantry Officer Course has failed due to medical reasons. The female volunteers are part of a study by the Marines to see if women can become ground combat leaders.

The Marines have not released the names of either woman, citing privacy concerns.

Defense Secretary Leon Panetta is expected to announce during a meeting of NATO defense leaders in Brussels Wednesday that Marine Gen. Joseph Dunford will be nominated to succeed Gen. John Allen as the top commander in Afghanistan, according to a defense official familiar with the decision.

How does a president bring the war in Afghanistan to an end? There are 68,000 American troops serving in the country as the war enters its 12th year.

The war hasn't been a major issue in the presidential campaign, and polls show American voters are tiring of the war. But the next commander in chief will find the Afghan war among the most difficult of many foreign policy challenges.

Both President Obama and Gov. Mitt Romney appear to agree on a date: the last day of December 2014. That's when the Afghan security forces are scheduled to takeover.

Women in the U.S. military have been flying warplanes for years, and recently began serving in artillery and tank units. But they're still barred from direct ground combat.

Now, for the first time in the course's 35-year history, the Marine Corps is putting the first women through its grueling Infantry Officer Course: 86 days crawling through obstacle courses, lugging heavy machine guns, navigating the woods at night.

Col. Todd Desgrosseilliers, the top trainer at Marine Base Quantico in Virginia, says there's a good reason the course is so tough that 1 in 5 Marines fail.

On this morning 150 years ago, Union and Confederate troops clashed at the crossroads town of Sharpsburg, Md. The Battle of Antietam remains the bloodiest single day in American history.

The battle left 23,000 men killed or wounded in the fields, woods and dirt roads, and it changed the course of the Civil War.

It is called simply the Cornfield, and it was here, in the first light of dawn that Union troops — more than 1,000 — crept toward the Confederate lines. The stalks were at head level and shielded their movements.

Gunmen wearing Afghan police and army uniforms have killed 40 U.S. and NATO troops so far this year, and the top American commander in Afghanistan says there is no single reason — and no simple solution.

Taliban infiltrators, disputes between NATO and Afghan security forces, and even the timing of Ramadan, the Muslim holy month, are all factors, according to Gen. John Allen.

"We think the reasons for these attacks are complex," says Allen, who spoke by video link from Kabul on Thursday. Ten of the American deaths have come in just the past two weeks.

The top officer in the U.S. Air Force, Gen. Norton Schwartz, is stepping down Friday after four years on the job.

Schwartz got the job after his predecessor was fired for — among other things — clashing with his Pentagon bosses over how many fighter jets the military needs.

Schwartz is most likely to be remembered for pushing another kind of aircraft: drones.

At this moment, dozens of these unmanned aircraft are flying high above Afghanistan.

Just don't call them drones when speaking with Schwartz.