Question

Why were John Kerry and other returning Vietnam veterans upset with the United States government

Answer 1

As the opposition of the public opinion to the war grew in the United States, in great part because of the massive TV coverage portraying the horrors of war in every U.S. household, the protests and insults against the U.S. servicemen returning from their tour of duty in Vietnam also increased. Formerly, World War I, World War II and Korean War veterans returning home were enthusiastically welcome and honored by the civilian population. Conversely, the rumors of countless war crimes and atrocities committed  by U.S. servicemen against both innocent civilians and enemy combatants and largely unaddressed, let alone punished by military authorities, in flagrant violation of the Geneva Convention protecting civilians and prisoners of war, stirred the unpopularity of the soldiers returning from Vietnam who were usually called "baby killers" and "assassins."

The harsh treatment veterans received as they came back home prompted them to establish organizations such as Veterans Against the Vietnam War, which John Kerry joined in 1969. On behalf of his colleagues, John Kerry testified before the Congress and denounced all the crimes that had been passed out by both U.S. military and civilian authorities, which had unfairly harmed the reputation of thousands of veterans who had performed honorably during their tours of duty and made many of them feel ashamed to have served their country.