A number of years ago I was at an antiwar protest in St. Petersburg, FL where one of my fellow protesters was holding a sign that said, "The U.S. military is killing innocent people in Iraq."
Within moments, a person who said he was in the Army began screaming at the protester saying, "I just came back from Iraq where I was fighting for your freedom. Without the military you wouldn't have the right to protest." The protester, himself an Army veteran, replied, "you look good for someone who is over 200 years old, because that was the last time the U.S. fought a war for freedom."
The returning soldier tried to argue that the attacks on 9/11 were a threat to the Constitution, but his argument was weak and he eventually scurried off. I don't know if he really felt he went to Iraq to protect free speech, or he was just angry that we were protesting something he believed in (which would have been ironic), but he wasn't the first or last person I've heard claim that the U.S. fights wars overseas to protect the rights of U.S. citizens.
In fact, I'm hearing it a lot today in the context of players in the NFL taking a knee while the National Anthem is played before games. "You're disrespecting the military -- the men and women who are fighting for your right to protest" is the ultimate rationale offered by those who disagree with the players peaceful protest. Sadly, many in the NFL take the bait and say, "I thank the military for their service and for giving me the right to protest." The U.S. war machine couldn't hear sweeter words as NFL players are unwittingly being used by the war machine to glorify the military, thus normalizing U.S. wars abroad. (As a side note, NFL players' protest is not actually covered by the First Amendment -- it only applies to public space, not privately-owned spaces such as NFL stadiums.)
In the first eight months of his presidency, Donald Trump's military has dropped bombs in seven countries . Can anyone explain to me how any of those bombs were dropped to protect American's First Amendment rights? (Note: Barack Obama's military also dropped bombs in the same seven countries: Afghanistan, Iraq, Pakistan, Somalia, Yemen, Syria and Libya.) Does anyone really think that Saddam Hussein, Osama bin Laden, Kony, al-Shabab, Muammar Gaddafi or even ISIS had/have the intention, let alone the ability to invade the United States, take over the government and shred the Bill of Rights? If so, I'm open to listening to the reasoning.
Yet somehow to this day it appears that this misguided believe remains the norm. It can be argued that the U.S. military fights overseas for empire, for oil, or for corporations. But I'm still waiting for a logical argument that the U.S military fights wars in foreign lands to protect the rights given to Americans in 1791.