A U.S. Air Force C-123 sprays herbicides on dense jungle beside a South Vietnamese highway on May 18, 1966. This aircraft is the last in a formation of three. Spray from the other two planes can be seen ahead. U.S. Air Force via AP hide caption

itoggle caption U.S. Air Force via AP

The ferry pulls in to Friday Harbor, the only incorporated city in San Juan County, Wash. Veterans will often travel the hourlong ferry ride to reach VA services here. Patricia Murphy/KUOW hide caption

itoggle caption Patricia Murphy/KUOW

Grant County Veterans Service Officer Bob Kelley (right) works with World War II Army veteran Frederick Kern at the Grant County Government Building in Marion, Ind., on Monday. Aaron P. Bernstein for NPR hide caption

itoggle caption Aaron P. Bernstein for NPR

George Murray, who served in Vietnam, was able to access his medical benefits from the U.S. Department of Veteran Affairs relatively easily while living in Boston. But veterans living in other parts of Massachusetts, like Cape Cod, have more difficulty. Across the U.S., VA data show the unevenness in its benefit spending. Jesse Costa/WBUR hide caption

itoggle caption Jesse Costa/WBUR

Sen. John McCain discussed the Veterans Choice Act at a news conference on Tuesday, with fellow Arizona Republican Sen. Jeff Flake. Mark Wilson/Getty Images hide caption

itoggle caption Mark Wilson/Getty Images

Tom Tarantino, chief policy officer at Iraq and Afghanistan Veterans of America, speaks at a news conference on Capitol Hill Thursday about holding the Department of Veterans Affairs accountable. Mark Wilson/Getty Images hide caption

itoggle caption Mark Wilson/Getty Images