Reporting from Iraq is always dicey. Dozens of journalists have been kidnapped, injured or killed since the U.S. invasion almost four years ago.

But network and cable news reporters say the escalation in sectarian violence, coupled with uncertainty about the future U.S. role in Iraq, have prompted Iraqis to be more wary of them and have made a dangerous assignment even more perilous.

Reporters say their ability to paint a full picture of Iraq is increasingly difficult because of safety restrictions that they or their news organizations have imposed.

"We now have the 15-minute rule: We never stay anywhere longer than 15 minutes to reduce the chance of kidnapping or attack, CBS' Elizabeth Palmer says.

"If I go to somebody's house, I do so invisibly," Palmer says. "And I have to be conscious of the people I show in my stories, because just putting them on the screen might effectively be exposing them to death."

Says ABC's Dan Harris: "I can't casually make a decision locally with my producers, like 'Oh, let's embed for the day' or 'Let's go on this raid.' We have to run it up the flagpole internally, and it's a subject of real discussion about what type of vehicle we're in, what protection we'll have and is it worth the risk.

"Every time we're driving around in one of their vehicles, all I can think about is roadside bombs."

Those bombs, which severely injured ABC's Bob Woodruff and CBS' Kimberly Dozier and killed CBS cameraman Paul Douglas and soundman James Brolan, have made media outlets and reporters much more cautious.

Fox News' David Mac Dougall says he'll no longer ride in military Humvees, in favor of heavier armored carriers. "Before, we were more inclined to go on patrols," says Mac Dougall, who spent his fourth straight Christmas in Baghdad. "Now, we are actively thinking, 'Is this patrol worth it? What do we gain from this?' "

Simply being seen with a foreigner is now enough to get an Iraqi killed by insurgents, reporters say. As such, normally talkative Iraqis are now more reserved.

"Where once you could rely on the general population to at least watch your back, to alert you to what danger may be around you, you can no longer, be it out of fear and intimidation or a dwindling in sympathy or empathy for us and our position," CNN correspondent Michael Ware says. "In terms of the insurgency, we are seen as legitimate targets: part of the problem, not the solution."

Harris, who finished his sixth visit to Baghdad on Dec. 15, says the biggest change is how profoundly "pessimism is taking hold." In a story for ABC's "World News Tonight," Harris reported on how his once "gung-ho" Iraqi translator now plans to flee the country.

Harris says most Iraqis remain friendly and gracious. "In the course of an interview, they may speak with real venom about the action of my government, but they'll still invite you in for tea."

That said, there are "plenty of bad guys who would gladly and quickly kidnap or kill you," Harris says. "I said to my driver casually the other day, 'If I get out of this car, take off my flak jacket or get rid of all my security and walk down the street, how long would I last?' He said, 'Four or five seconds.' "

Three years ago, Mac Dougall says, he and his producers would routinely hop in a car and drive to downtown Baghdad for dinner.

"Sure, we'd go with armed guards, but we'd head to an Italian restaurant with red-and-white-checked tablecloths, have a bottle of red wine, there'd be Italian music playing, and apart from the Iraqi waiters, you could have been anywhere in the world," Mac Dougall says.

"I'm not eating Italian food these days."

Knowing the dangers, why do reporters continue to go back? It's the biggest story on the planet, they say.

"When you are watching American soldiers, guys from Kansas, and Iraqis, doing enormous acts of heroism, to not cover it, to go somewhere more comfortable — safer — it just feels you wouldn't be doing those people justice," says NBC's Jane Arraf, who has reported from Iraq since the days when Saddam Hussein ran the country.