Next week is the start of the fall semester at the college where I teach journalism, and early on I'll be telling students which books to buy, what kinds of stories they'll be covering and how to write a lede.

But at some point in the semester I'll give what I've come to think of as The Talk, the one where I explain to the assembled 18-year-olds that journalism can be not just a very stressful, taxing and time-consuming job, but also a very dangerous one.

Of course, that was made clear for the umpteenth time when Islamic militants this week released a grisly video of freelance American  journalist James Foley being beheaded. Foley disappeared in November 2012 in northwest Syria, which he was covering at the time for GlobalPost.

As grim as Foley's execution was, it wasn't the only recent example of journalists facing danger. Several reporters have been arrested or harassed by police while covering the ongoing demonstrations in Ferguson, Missouri, over the shooting death of unarmed black teenager Michael Brown.

And of course, in much of the developing world, local journalists take their lives into their own hands on a daily basis. They face jail, beatings, torture and worse for daring to tell the truth about dictatorial government regimes, corrupt business interests and criminal organizations. It happens everywhere, from China to Iran to South America.

I'd like to say things are much better here in the U.S., but as we've seen in Ferguson, reporters can be harassed simply for exercising their First Amendment rights.

Meanwhile, the Obama administration, in its zeal for protecting secrets, has a less-than stellar record in its dealings with the fourth estate.

Right now, though, that pales in comparison with the death of Foley, who by all accounts was a supremely dedicated journalist who, even as a freelancer lacking the institutional backing that comes with being a staff correspondent, still made a point of venturing to the most dangerous places on the planet.

Indeed, before being kidnapped in Syria, Foley had covered the equally dangerous Libyan conflict, and was taken captive there as well. Later, after his release, he spoke to a group at Northwestern University’s Medill School of Journalism, where he'd earned his master’s degree. According to The Washington Post, Foley recalled that one of his editors had told him not to go to Libya. Foley's response? “I had to go.”

I know when I have this talk with my students, someone will ask the obvious question. Why? Why do they do it? Why do they go to war zones and extremist strongholds? After all, no one forces you to cover a combat zone. Everyone who goes, goes voluntarily.

There are many reasons. Some reporters know they can quickly make a name for themselves in the news business by covering a war. Some become addicted to the adrenaline rush of dodging bullets.

But most do it simply because they know there's a story to be told, and like Foley they feel they have to tell it, understanding all the while the dangers of what they do.

They are not soldiers. They carry no weapons. Like reporters everywhere, they'll bring the usual gear - a pen, notepad, a digital camera, phone and maybe a press card. Armed with nothing more than courage and the tools of their trade, they go.

And many, too many, die; 39 journalists have been killed covering the Syrian civil war since March 2011; another 22 have died in Iraq during the same period.

And yet they keep going. From Wall Street Journal reporter Daniel Pearl to Al Jazeera correspondent Mohammed Al-Horani, from Times of London writer Marie Colvin to Al-Arabiya correspondent Sabah Al-Bazi, they venture into the heart of places most of us wouldn't dream of visiting, just to tell us what is happening there.

For that, and for them, we should be grateful. That's what I'll tell my students.

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