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UPPER MARLBORO, Md. — There are a lot of reasons people love their AR-15 semiautomatic rifles, and it doesn't much matter to them what the haters say.

For some, the gun is a tool, a finely tuned machine that can cut down an animal or intruder, or pierce a distant target, with a single precise shot.

For others, it is a toy, a sleek beast of black plastic and metal that delivers a gratifying blast of adrenaline.

And for many, it is a symbol, the embodiment of core American values — freedom, might, self-reliance.

“There are very few things that serve such a great form and function, and look cool,” said Daniel Chandler, 26, an AR-15 owner here in suburban Maryland. When he takes his AR out of its case at a shooting range, he smiles like he just unwrapped a gift. “There are few things you’ll find that are wonderfully appealing to look at, wonderful exercises in mechanical engineering, and that could save your life.”

This is the side of the AR-15 that many don’t see, or ever consider.

Because an AR-15, or a variant, was reportedly used in several mass shootings — including Aurora, Colorado; Newtown, Connecticut; San Bernardino,California; Sutherland Springs, Texas; Las Vegas and Parkland, Florida, in which a total of 154 people were killed — this civilian sibling of a military assault rifle is an exceptionally polarizing product of modern American industry. The AR-15 and its semiautomatic cousins — they shoot one round for each pull of the trigger ─ incite repulsion among those who see them as excessive, grotesque and having no place on the civilian market.

It is the focus of multiple attempts at prohibition, which in turn has prompted people to run out and buy more. Such “panic buying” drove sales of AR-15s to record levels during the presidency of Barack Obama and the 2016 presidential campaign. Gun merchants say some buyers are also driven by a fascination with a weapon used in notoriously heinous crimes.

Fears of a ban have subsided under gun-friendly President Donald Trump, and so have sales; gun makers are in the midst of a year-long slump that has driven down prices for AR-style rifles. Those discounts appear to have driven a record number of Black Friday gun background checks.

Devotees say the AR-15 has been wrongly demonized, arguing that the vast majority of owners never use it in a crime, and that despite the rifle’s use in mass shootings, it is responsible for a very small proportion of the country’s gun violence.

Thanks to that ardent following, and shrewd marketing, the AR-15 remains a jewel of the gun industry, the country’s most popular rifle, irreversibly lodged into American culture.