Over the past seven years more than 1.5 million American troops have served in Afghanistan and Iraq. These men and women have served their nation with honor and distinction. Yet, there is growing evidence that our nation is failing to properly treat hundreds of thousands returning combat veterans, many of whom may end up homeless and on our streets.

Faced with unforeseeable and anonymous threats in the forms of improvised explosive devices and car bombs, our combat troops today are subject to prolonged psychological stress different from previous conflicts. It should not be surprising to anyone that the costs of the Iraq and Afghanistan wars will continue for years to come.

Unfortunately, our nation has not faced up to the needs of our returning troops and there is a looming crisis of homelessness among veterans.

A recent study of soldiers who served in Iraq and Afghanistan conducted by a respected, independent research organization found that roughly 300,000 of our returning troops suffer from post traumatic stress disorder or severe depression.

Shockingly, only half of our nation's Veterans Affairs medical centers currently offer PTSD counseling and six of seven surveyed cannot handle their current case load. This is compounded by the fact that there is only one VA psychologist for every 1,100 soldiers who recently served their country in a war zone.

As a Vietnam veteran, I have seen the emotional and psychological burdens that war imposes. Many Iraq and Afghanistan veterans will have difficulty re-adjusting. Others will not seek help, fearing repercussions to their careers. Thousands will be lost to a system that is woefully under-equipped to grapple with illnesses that are difficult and costly to diagnose and treat.

Vietnam-era veterans understand that homelessness can begin with PTSD. We do not want to see today's soldiers returning from war zones ending up on the streets like so many of our comrades have.

The need to address the lack of mental health care for our military veterans has never been more urgent. To see the costs of inaction you may not have to go far from your own home.

On any given night, 200,000 veterans, including 3,000 who served in Iraq and Afghanistan, are living on the streets of our nation. At some point during this coming year, 400,000 men and women who served this nation in uniform will experience homelessness. Approximately one of four homeless men are veterans, making veterans seven times more likely to be homeless than their civilian counterparts.

With this enormous problem staring at us, it is disappointing that the presidential candidates have paid it little attention. I've watched more than 20 debates and have not heard one question about the problems facing the returning American veterans, let alone the growing epidemic of homeless veterans.

I am sure the candidates are not aware of it, but in Pennsylvania each night there are as many as 5,000 homeless veterans, yet the VA currently funds only 332 beds in the state dedicated to providing them a place to sleep. Congress needs to double the number of beds and the per diem allowance for veterans' facilities that provide shelter for homeless veterans, as well as provide PTSD counseling at every VA center.

Fortunately, the Pittsburgh area is home to some highly regarded facilities that work to transition homeless veterans back into society where they belong. The Vietnam Veterans' Leadership Program provides housing and supportive services for more than 100 homeless veterans every day.

In Cowansville, the Mechling-Shakley Veterans Center has offered a hand up to hundreds of veterans who are sober and willing to work by approaching their needs holistically. The center helps these veterans with medical or mental-health needs, and with substance-abuse counseling and job training in a tranquil, rural setting.

Both facilities operate these outstanding programs on only $30 per bed per day from the federal government and rely mostly on the support of local individuals.

The presidential candidates need to wake up and hear our call. Unless the returning Iraqi and Afghan veteran get the kind of treatment needed for those returning from battle zones, the epidemic of homeless veterans will grow to unprecedented proportions.