I remember when I first heard a Vietnam veteran’s story. I was captivated as he described his desperate attempts to render aid as his dying best friend bled out in front of him. Half a world away and decades later in 2008, the scene was still painful for him to recall. But the most shocking part of the story was his return home.

My heroic friend described having to change out of his uniform before roaming American streets – or else he’d be subject to threats. I was only 15 and I simply couldn’t believe that civilians would spit on, curse and even attack returning veterans. And all this happened on American soil.

Serving in the Army today, my peers and I have a very different experience. When we wear our uniforms in public we get pats on the back, offers to pay for our meals, and warm remarks expressing gratitude for our service. Certainly, much has changed for the better. But sometimes I wonder if things will always be this way.

If anything is clear in American culture, it’s that yesterday’s taboo is today’s status quo. The more we normalize disrespect to the national anthem, applaud pledge of allegiance protests, and entertain discussions about how democratic ideals are somehow inherently flawed – the easier it will be to disrespect the people who are sworn to protect those ideals. In other words, what’s preventing Americans from mistreating service members in the future as a form of protest?

The more we normalize disrespect to the national anthem, applaud pledge of allegiance protests, and entertain discussions about how democratic ideals are somehow inherently flawed – the easier it will be to disrespect the people who are sworn to protect those ideals.

In our polarized country, everything is potential political fodder. Sports, entertainment, holidays, national tragedies – things that once unified us – are now sources of division.

Military service is still one of the few things in our society that both sides of the political spectrum can agree is worthy of respect. Supporting the armed forces is about the last inch of common ground left in America. But how much longer until that ground is under siege by those that who seek to divide us?

To be clear, I’m not calling for Americans to blindly worship the military. As Army veteran David French aptly pointed out in a recent piece in the National Review: “Not everyone in the military is a hero. The mere act of donning a uniform does not make you any better than any other American.”

And I agree with French’s assertion that “loving the troops and supporting the military means holding both accountable.” But military accountability is an entirely different issue from the growing anti-American sentiment percolating through our culture.

Consider a recent poll conducted by the Victims of Communism Memorial Foundation, which found that nearly half of U.S. millennials would rather live under a communist or socialist regime than a democratic country.

Amazingly, one in five Americans in their 20s view Soviet dictator Josef Stalin as a hero, while over 25 percent thought highly of his predecessor Vladimir Lenin and North Korean dictator Kim Jong Un. And an appalling 40 percent believe in restricting some First Amendment freedoms.

“Millennials now make up the largest generation in America, and we’re seeing some deeply worrisome trends,” said Marion Smith, the executive director of the foundation.

Worrisome is an understatement.

More and more citizens fail to understand the importance of democracy and thus can’t see value in patriotism. That leaves them more susceptible than ever to false narratives about what it means to be an American. And even worse, such narratives could easily lead them to more radical forms of protest.

Concerned Americans – Democrats, Republicans and everyone else – should work together to educate our fellow citizens and reverse the flow of ignorant ideas that continue to gain momentum. As Thomas Jefferson cautioned us: “If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be.”

American culture is not far removed, in either time or ideology, from the days when U.S. soldiers, sailors, airmen and Marines were harassed by their own countrymen when in uniform.

On this Veterans Day, the mistreatment of American troops remains a red line that few dare to cross. But with every new protest, it seems that line gets a little less clear.