When we raised our collective hands and swore an oath "to protect and defend the Constitution of the United States against all enemies, both foreign and domestic," we basically wrote a blank check to our fellow citizens and our country. Our part of that contract meant that we pledged to make ANY sacrifice - to include our bodies and lives - to uphold our oath. One of the many parts of the Government's part of that contract was healthcare (albeit by intimation rather than in writing).
Non-veterans have no idea what those sacrifices entailed - being on call 24/7/365, willingly going into harm's way, working 20-hour days for weeks on end, and doing all sorts of things required by the job that are inherently damaging to health and well-being. I personally performed a multitude of duties on a gunnery rotation to Grafenwoeher, FRG where I got 11 total hours of sleep during the entire 11-day period that the gunnery lasted. Six of those hours came on the 10th night. One of the big tools that the re-enlistment NCO's used to get soldiers to stay in the military was "free healthcare for life" for those who stayed around to retired.
In the 1980's Congress became alarmed at that state of affairs. Their reaction to this was to push "TRICARE for Life." That means that at age 65, ALL retirees and spouses would have MEDICARE as their primary health insurance and TRICARE became secondary health insurance. When some retirees who were WWII, Korea, and Viet Nam veterans sued over the loss of their earned benefit of free lifetime healthcare, the Federal Courts ruled that the promise of free lifetime healthcare was an IMPLIED benefit rather than a contractual benefit.
General Omar N. Bradley was once the Secretary for Veterans Affairs. His efforts helped disabled veterans and retirees get suitable healthcare as a return on their sacrifices, injuries, and damaged health. My experience with the Veterans Administration Medical Centers (VAMC) has been a mixed bag. The physicians, nurses, and healthcare providers are - largely - quite good or excellent. The administrators that support these professionals by acting as gatekeepers, leave much to be desired. Many of these folks have the attitude that they are doing a favor to the veterans simply by showing up every day. I know of an Administrator in the Pittsburgh, PA who stated, in a staff meeting, that she would NOT get her flu shot during the kick-off publicity event because she did not want to be close to all those "smelly, old veterans." Sadly one can see this attitude, in many instances, on a daily basis at any VAMC in the entire system.