Once upon a time, President Barack Obama believed that sick Americans should have access to medical marijuana. Today, Obama says that Iraq and Afghanistan veterans suffering from Post-Traumatic Stress Disorder should have access to everything but medical marijuana—including heavy duty prescription painkillers.

Obama's refusal to consider treating PTSD with marijuana has led some wounded veterans to defy their doctors, in essence compromising their treatment, and for others to leave the Veterans Affairs system altogether.

Earlier this year more than 25,000 vets and their supporters led by Veterans for Medical Cannabis Access (VMCA) signed a petition on WhiteHouse.gov titled, "Allow United States Disabled Military Veterans access to medical marijuana to treat their PTSD." What they got in the way of a response was a complete and total brush-off.

From Drug Czar Gil Kerlikoswke, director of the Office of National Drug Control Policy:

Many brave men and women who have risked their lives in service to our country are now suffering from physical, mental health, and substance abuse problems. We have an obligation to care for our military families and veterans and to improve their lives by increasing access to vital treatment services specifically geared toward our military heroes. While the Administration continues to support research on what parts of the marijuana plant may be used as medicine, neither the Food and Drug Administration nor the Institute of Medicine has found smoked marijuana to meet the modern standard of safe or effective medicine. We will continue working with our partners in the medical community to ensure that veterans have access to science-based medical treatments and get the help they and their families need.

You can read VMCA's response here.

Kerlikowske's response, meanwhile, suggests that marijuana is plaguing vets returning from Iraq and Afghanistan. But that's simply not true. A report released by the Centers for Disease Control in 2008 (and revised in 2011) doesn't even mention marijuana. It names alcohol and prescription drugs as the most abusive substances for veterans:

Prescription drug abuse doubled among U.S. military personnel from 2002 to 2005 and almost tripled between 2005 and 2008. Alcohol abuse is the most prevalent problem and one which poses a significant health risk. A study of Army soldiers screened 3 to 4 months after returning from deployment to Iraq showed that 27 percent met criteria for alcohol abuse and were at increased risk for related harmful behaviors (e.g., drinking and driving, using illicit drugs).

That brings us to Emanuel Herrera, a National Guard member who was severely injured by a roadside bomb in Iraq in 2006:

Emanuel Herrera returned from war addicted to painkillers and barely able to tolerate his children's voices. Last year, despite warnings from medical staff at the local veterans hospital, he began to smoke pot legally under the state's new medical-marijuana program to cope with the physical and mental pains of combat. "My doctors shunned me and didn't approve of me doing it," said Herrera, a Purple Heart recipient. "One doctor said I could get some repercussions for doing it. But I did it legally. And I know for a fact—I'm a walking testimonial—that it works." "My family would tell you that, before this, sometimes I was like a madman," he said. "I kicked in my daughter's door and almost threw a bar stool out of the window. Not only has it helped my with anger and irritability issues, it's also helped keep my spirits up."

Here's another veteran interviewed by the Arizona Republic:

Iraq veteran Cory Woodstock believes the VA abandoned him after he began smoking marijuana illegally. He suffers from a traumatic brain injury, PTSD, depression and physical pain.

While serving in the military, the security convoys he rode in were involved in three bomb attacks within 38 hours.

By the time the Purple Heart recipient returned home to Apache Junction, he was on 23 prescriptions, taking 57 pills a day. In 2009, he smoked marijuana for a short time after veteran friends told him it would help stop the voices in his head and the pain radiating through his body. But once the pot showed up in his urine tests, he said, his VA doctor cut him off all prescriptions, which he still needed to manage his pain. He stopped ingesting marijuana, afraid federal officials would strip him of his benefits because they still consider pot to be illegal. He sought treatment outside the VA system but said it hasn't helped as much as the marijuana did. "It was an experiment, and it worked," he said. "I was able to sleep. I wasn't so conscious about not being able to speak (well). I told the doctors I tried it and it helped. They said it voided my contract with the VA."

And another veteran, this one from Maine:

Begin told doctors in federal health centers high-grade medical marijuana was his only hope for tamping down the innumerable nightmares, flashbacks and fears that followed him from the battlefield. "My mood's stable now—no peaks and valleys, just stable ups and downs," he said. His mother, Anna—"a little bit apprehensive" about medical marijuana at first—is a believer. "When he started the marijuana, it was like having my son back," she said. Doctors in the federal veterans' health care system aren't as convinced. The substance remains illegal under federal law, and guidelines for federal health centers don't support medical marijuana. That ended Begin's relationship with the federal health system.

Two years ago, the Department of Veterans Affairs came halfway to grips with veterans' preference for marijuana, and released a directive stating that while VA doctors can't recommend medical pot, they also can't deny treatment to vets who use medical marijuana in states where it's legal. But the halfway approach clearly isn't cutting it.