We went to see “Tropic Thunder” the other day to decide for ourselves what the ruckus is all about. As is more frequently the case these days, I came away with decidedly mixed feelings.

“Tropic Thunder” is the new Ben Stiller movie about making a movie about the Vietnam conflict. It boasts big stars — Robert Downey Jr., Jack Black, Nick Nolte and Tom Cruise in addition to Stiller — a convoluted plot, plenty of blood and blue language and enough jabs at current political correctness to knock it out. It’s the latter that’s gotten it into trouble.

Specifically, it’s the fun poked at the intellectually disabled that has the likes of Special Olympics and a score of other organizations for the intellectually disabled calling for a boycott of the movie. I assume they’re most offended by a pair of scenes, one of which describes a movie Stiller’s character starred in called “Simple Jack,” and another in which Downey’s character tells Stiller just what was wrong with that movie.

My daughter Mary, who is intellectually disabled, nearly walked out. She finds the term “mentally retarded” offensive in the extreme, as do most of her intellectually disabled peers. As she says, saying someone is mentally retarded is tantamount to saying they’re incapable of learning, and nothing could be further from the truth. And even the most insensitive among us recognizes the epithet “retard” for the insult it’s always meant to be.

People like Mary know just how wrong the stereotypes can be. Everyone, even the most profoundly handicapped, is capable of learning, and the intellectually disabled know that. That some may require more teaching or a different way of approaching things does not mean they don’t learn. Mary knows that. Her mother knows that, and so does anyone who knows someone with an intellectual disability.

These days, “mentally retarded” is something of a legal definition in any event. It’s used by government agencies to determine the level of services to which a person is entitled. If you’re not mentally retarded and simply have learning disabilities, you may be entitled to less help as an adult than you would otherwise be.

The definition is set out in the federal Bilingual Education Act and elsewhere. To qualify, an individual must have both significantly subaverage general intellectual functioning and deficits in adaptive behavior. Moreover, the problems have to have been evident early in a child’s life. In other words, low intelligence alone is not enough to make a person retarded. He or she must also have other problems, physical limitations or judgment problems or something that makes it difficult to do the things the rest of us take for granted. It’s those limits that go a long way to explaining why men and women with intellectual difficulties are so proud of their jobs — just having them and keeping them are far greater accomplishments than for most workers, and they’re a clear symbol of the “normal” world.

But back to “Tropic Thunder.”

In my mind it’s not the use of the language and the demeaning images of the intellectually disabled that make it so objectionable, though I agree the latter were pretty darned bad — the “Simple Jack” character is a freckle-faced doofus who probably is incapable of learning, a guy who calls tears “rain from my eyes,” among other things.

No, it’s that there is absolutely no refutation of the stereotypes that bothered me most — though it was the language that was most distressing to my daughter. Robert Downey Jr. in blackface was balanced by a genuinely African-American actor, Brandon T. Jackson, who called him on his behavior at every turn.

Not a single character in the movie, not one, ever bothered to mention that an intellectually disabled person he knew was nothing like Simple Jack — or that anyone might have found the portrayal offensive. It and the language that went with it were simply accepted, simply funny, and no one once said that either was simply wrong.

I work in a part of the news business that has little room for political correctness, that generally abhors the hypersensitivity that allows us to describe a murderer as simply “troubled,” as if a good night’s sleep will correct his clear lack of moral compass. At the same time, watching Mary’s visceral reaction to the words “mentally retarded,” to flinch myself when someone calls someone else a “retard,” makes me understand completely the response to “Tropic Thunder.” Stiller and friends were careful to take the sting out of the other nasty stereotypes in the movie; I only wish they’d bothered to do the same for the intellectually disabled.