Veterans are still suffering from the illnesses caused by the toxic herbicide used during the Vietnam War. They want to know why the VA doesn’t offer more help.

Most of the media coverage of President Obama’s trip to Asia has focused on whether the president should apologize to Japan for the United States dropping an atomic bomb on Hiroshima at the end of World War II.

According to Obama administration officials, there are no plans to apologize for this bombing, which took the lives of more than 100,000 Japanese civilians.

But might the same question be asked about Agent Orange in Vietnam?

The U.S. military sprayed the toxic herbicide, along with other deadly defoliants, over more than 20 percent of South Vietnam between the early 1960s and early 1970s in an attempt to flush out their enemies.

Agent Orange doesn’t get as much press as it used to, but its profound lingering effects remains a significant international public health issue in 2016.

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Hundreds of thousands of American veterans of the Vietnam War have died, or are still suffering because of exposure to dioxin, the deadly toxin in Agent Orange.

Exposure to it can cause multiple cancers as well as other diseases and health problems.

The Vietnam Red Cross estimates that Agent Orange has affected 3 million Vietnamese people, including at least 150,000 children. Babies in Vietnam are still being born with birth defects due to Agent Orange.

The United States and Vietnam set up a decontamination effort several years ago in Da Nang, a city in Central Vietnam that was once the site of a U.S. airbase that stored Agent Orange. It was the most toxic of 28 reported dioxin “hot spots” in Vietnam.

But because of chilly relations between the United States and Vietnam over the past four decades, efforts to clean up Agent Orange have been slow and minimal.

Could that change when Obama visits Vietnam for the first time on Sunday?

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The Department of Veterans Affairs (VA) presumes that any of the 2.8 million U.S. veterans who had “boots on the ground” in Vietnam from 1962 to 1975 were exposed to dioxin-contaminated herbicides, including Agent Orange, which was developed by Monsanto and Dow.

It took two generations and a lot of heartache among the Vietnam veteran community, but the VA’s “presumptive list” of diseases that are caused by exposure to Agent Orange now includes everything from non-Hodgkin lymphoma, prostate cancer, and multiple myeloma to Parkinson’s disease and ischemic heart disease.

But many veterans exposed to Agent Orange and their loved ones are still fighting for the disability coverage they believe they have earned.

The VA is denying disability benefits to most Vietnam veterans who are suffering or have already died from glioblastoma, a particularly deadly form of brain cancer that is not on the VA’s presumptive list.

“It’s absurd that it’s had to go this far,” said Kristi Anthony, a paralegal whose father, Danny Lee Howell, was exposed to Agent Orange while stationed during the war at Thu Duc, a military air base near Saigon.

Howell died of glioblastoma in February 2014.

“Causal relationship between my dad’s brain cancer and service-related connection is clearly established,” said Anthony, who’s still fighting the VA on her own to receive the benefits her father sought for his family. “Glioblastoma cannot be disassociated from my dad’s herbicide exposure in Vietnam.”

Robert Walsh, an attorney who’s represented hundreds of veterans in disability cases with the VA, said the VA approves some but rejects most.

“The VA has granted benefits to veterans who were exposed to Agent Orange and have glioblastoma a number of times since at least 2004,” Walsh said. “If VA accepts one medical opinion, if they grant just one case, how do they justify forcing all the other veterans to relitigate it over and over?”

Nearly a dozen men and women in various stages of the fight for their sick or their deceased husbands, brothers, fathers, and grandfathers with glioblastoma spoke exclusively with Healthline.

Each person interviewed expressed hope that President Obama’s trip will shine new light on the issue of Agent Orange exposure, and each insisted that the VA is arbitrarily denying disability benefits to some veterans who were exposed while granting them to others.

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Agent Orange is still being discussed in Washington this week.

Christopher Gibson (R-NY) offered an amendment today to the 2017 Military Construction-VA Spending in support of Vietnam veterans exposed to Agent Orange.

Specifically, Gibson’s amendment supports the sailors who were stationed offshore during the Vietnam War. They were also exposed to Agent Orange and are now sick and dying as a result.

They are also having trouble getting their illnesses related to Agent Orange covered by the VA.

“Their loyalties were never divided. They did everything they could every day to serve our nation,” Gibson said on the floor of the House of Representatives on Thursday morning. “What developed over that time was that they became sick, they were exposed to Agent Orange.”

Gibson noted that 320 of his colleagues on both sides of the aisle agree with this amendment. He said that while this nation chose to defoliate in Vietnam with Agent Orange, “what we learned is that there is a direct link with nine maladies including cancer and diabetes and Parkinson’s.”

He concluded, “Regardless of the difficulty of the fight,” he said, “we will never turn our back on our servicemen and women.”

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Joshua Stephen Leach, a recently retired Air Force veteran who served four tours in Iraq and suffers from severe post-traumatic stress disorder (PTSD) and traumatic brain injury (TBI), was able to win his grandfather’s Agent Orange case.

But it was a tough battle.

Leach’s grandfather, Angelo Venniro, served in the Army for 20 years and did two tours in Vietnam, where he was exposed to Agent Orange.

A lieutenant who later retired as a major, Venniro bravely fought his glioblastoma, but died in May 2015.

The VA initially denied Venniro’s disability claim. But Leach kept digging through case files and learned the history of Agent Orange.

An investigator in the Air Force, Leach met with renowned brain experts such as Dr. James Battiste, Ph.D., an expert in neuro-oncology at the University of Oklahoma.

Battiste submitted written testimony to the VA for Leach’s case stating that exposure to Agent Orange is a “significant factor contributing to the development of brain malignancies.”

Battiste wrote that it is “highly likely” that exposure to Agent Orange might, “cause, aggravate, or at a minimum contribute to the development of malignancies,” which in Venniro’s case, “this includes brain tumor.”

Leach won his grandfather’s case on appeal, and the VA granted his family full service-connection benefits in April 2015, a month before Venniro died.

Leach said a lot of families lose when going up against the VA because “they aren’t armed with the information that will win their cases and they don’t know how to go about getting it as it is very technical. Plus, the VA and other aid groups will flatly tell you that you cannot win so right off the bat will discourage someone.”

Marine and Vietnam veteran Edward “Tommy” Evans, who was exposed to Agent Orange, died of glioblastoma in 2003.

It took six years for his widow, Sheree Evans, to see her late husband and his family be awarded service-connected disability coverage from the VA for his cancer.

Sheree Evans wrote a book about her fight for her husband, “By the Grace of God a Promise Kept,” and has become a leader in helping other families that are dealing with glioblastoma get the support they are seeking from the VA.

Thomas Temples, a Vietnam veteran exposed to Agent Orange who is fighting glioblastoma, recently won his case in court. But that doesn’t mean he’s actually won.

He’s still fighting with his VA regional office in Detroit to receive his benefits.

Walsh, who is Temples’ attorney, said his client won his VA claim for glioblastoma “because the science is overwhelming that the dioxin found in Agent Orange is the trigger at the molecular level for glioblastoma and many other cancers and diseases.”

Temples’ case was sent back to VA’s Regional Office in Detroit. It’s anyone’s guess if or when he will be compensated, Walsh said.

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Accompanying President Obama on this trip to Vietnam will be Secretary of State John Kerry, who knows all too well the harm Agent Orange can do.

During the Vietnam War, Kerry was a swift boat captain in the waters off the Mekong Delta, where he told this reporter for the first time in 2004 that he was exposed to Agent Orange.

Years after the war, Kerry spoke out on behalf of his Navy friend Giles Whitcomb, who was with Kerry on those boats and was also exposed to Agent Orange.

Whitcomb died of non-Hodgkin lymphoma in 2006. Kerry fought the VA to give Whitcomb’s family the benefits he felt they earned.

But on this trip to Vietnam, will Kerry continue to fight for America’s Vietnam veterans who’ve been exposed to Agent Orange? And will he reach out to the Vietnamese civilian population still suffering because of Agent Orange?

When asked this question, Katherine Pfaff, a spokesperson for the State Department, said Kerry would not be making any comment and referred Healthline to the trip announcement on the State Department’s website.

There is no mention in the announcement of any discussions of Agent Orange or anything else having to do directly with the Vietnam War.

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Larry Vetter, a Marine platoon leader during the Vietnam War, hopes and believes Kerry will discuss Agent Orange at one point or another during this trip.

Vetter, who returned to Vietnam for the first time eight years ago to reconnect with his past, stayed in Vietnam and subsequently joined the Da Nang Association for Victims of Agent Orange (AO)/Dioxin, which assists more than 5,000 Agent Orange victims in Da Nang.

“It would be a dream come true if the president and/or the secretary of state, a war vet himself, could make a stop in Da Nang and get a tour of the site at the old U.S. Air Force base, now the Da Nang International Airport,” he said.

Vetter said he is a firm believer in the goodness of the American people, but “they just do not know what happened here. Agent Orange was a horrible creation to use in warfare. It was no less than chemical warfare, the type of weapon we condemn others for using.”

Vetter said he hopes and prays that American leadership can realize what really happened in Vietnam.

“It’s time for reconciliation and cooperation between both countries and peoples,” he said.

When asked about glioblastoma and Agent Orange, a VA spokesman told Healthline, “Part of the answer is the explanation between direct service connection versus presumptives. Brain cancer is not a presumptive but that does not stop us from directly service connecting if the medical evidence gives us the medical nexus. Unfortunately, not all medical evidence we receive is equal thus some denials may occur for what appears to be the same condition. Basically, every case is unique and different than any other.”

The spokesman added, “As of April 21, 2016, there are 303 Vietnam veterans who are service connected for brain cancer — all direct service connection. (Not presumptives at this time.)”

But numerous people told Healthline that glioblastoma needed to be placed on the VA’s presumptive list.

“Glioblastoma is a specific type of brain cancer, but the VA lumps it in colloquially as brain cancer along with the other types,” said Leach, who noted that the cost of treatment is “astronomical.”

“I think it’s literally about the money,” he said. “There isn’t any other logical reasoning for it. Several studies have conclusively determined Agent Orange causes any and all cancers, something that a now-declassified report alluded to over 25 years ago.”

Leach called the VA’s stand on glioblastoma “just another insult on top of their injury to deny these claims. The cancer rate for anyone exposed to Agent Orange is far beyond that of a normal citizen. These guys were placed in Vietnam by our government, in a military effort. It’s not like they just went on a personal vacation and got sick.”

Leach said that every Vietnam veteran was exposed to Agent Orange.

“It’s not a presumption, it’s a fact,” he said. “It’s also a fact that it causes cancer at any anatomical site. This cannot be disputed. There is overwhelming medical evidence that supports that statement.”

The fact the VA has not placed glioblastoma on its presumptive list, Leach said, is a “slap in the face to American service members, their families, and the country itself.”

Leach concluded, “I fully expect my generation’s burn pits [in Iraq] to become our version of Agent Orange. I also expect the same failures to care for our country’s veterans to continue. We have already seen the proof.”