The government is taking what President Barack Obama calls "a long overdue step" to aid veterans with post-traumatic stress disorder, making it easier for them receive federal benefits.

The changes that Veteran Affairs Secretary Eric Shinseki will announce Monday fulfill "a solemn responsibility to provide our veterans and wounded warriors with the care and benefits they've earned when they come home," Obama said in his weekly radio and online address Saturday.

The new rules will apply not only to veterans of the Iraq and Afghanistan wars, but also those who served in previous conflicts.

No longer will veterans have to prove what caused their illness. Instead, they would have to show that the conditions surrounding the time and place of their service could have contributed to their illness.

"I don't think our troops on the battlefield should have to take notes to keep for a claims application," the president said. "And I've met enough veterans to know that you don't have to engage in a firefight to endure the trauma of war."

Veterans advocates and some lawmakers have argued that it sometimes could be impossible for veterans to find records of a firefight or bomb blast.

They also have contended that the old rules ignored other causes of PTSD, such as fearing a traumatic event even if it doesn't occur. That could discriminate against female troops prohibited from serving on front lines and against other service members who don't experience combat directly.

"This is a long overdue step," Obama said. "It's a step that proves America will always be here for our veterans, just as they've been there for us. We won't let them down. We take care of our own."

A study last year by the RAND Corp. think tank estimated that nearly 20 percent of returning veterans, or 300,000, have symptoms of PTSD or major depression.

A senior official at the Department of Veterans Affairs said the agency doesn't expect the number of veterans receiving benefits for PTSD to rise dramatically, as most veterans with legitimate applications for benefits do eventually get claims. The goal is simply to make the claims process less cumbersome and time-consuming, said the official, who would speak only on condition of anonymity ahead of the VA's announcement.

More than 240,000 female service members have been deployed to the wars in Iraq and Afghanistan, but for many, reintegrating into civilian life and trying to find employment is not within their reach.

The Department of Veteran Affairs has acknowledged that women are nearly four times as likely as men to end up homeless.

In Los Angeles, outreach efforts are under way to get them off the streets and into the VA's transition assistance program.


Margaret Ortiz's Story

People walked right by former Army Pvt. Margaret Ortiz when she was sleeping on the street, unaware that at one time drugs and alcohol weren't the most important things to her. Her comrades were. Ortiz drove a truck in Iraq — often volunteering for the missions no one else wanted.

"To help my soldiers and protect them," she says. "They were my family at the time."

Today, Ortiz, 28, is living at a transitional housing facility for female veterans at U.S Vets, a nonprofit in Long Beach, Calif. She's one of the lucky ones, according to Dr. Diane West, who runs the Advanced Women's Program here.

"A lot of the women have no idea that there's a place for them. They're living in their car with their kids. It's really, really sad," West says.

There are 43 women in residence — and there's a waiting list.

"Women are being discharged from the military without the resources or the understanding of where to go to get jobs," West says. "And most of them coming here have some kind of mental problem."

Ortiz has been diagnosed with post-traumatic stress disorder. After returning from the war zone, where she dodged mortar fire and IED blasts, it was the little things that got to the former truck driver — like stop lights and trash on the street. That's because, she says, trash would usually have an IED in them. "So that just makes me nervous ... and big crowds."

Ortiz pauses and looks out the window. She says talking about what happened in Iraq can sometimes bring on nightmares.

"You just want to forget. And some of the stuff that happened, you'll just take it to take to your grave 'cause you don't want to talk about it," she says.