LAS VEGAS — The problem with Miley Cyrus isn’t that she has broken bad. It’s that she’s so confusing.

One day, she’s sexualizing herself without actually being sexy, putting her hair up in double buns like a baby devil’s stubby horns and sticking her tongue out like a cartoon-character Calvin making faces at his stuffed tiger.

The next, it seems, she’s singing Wrecking Ball, a devastating piece of heartbreak pop that ranks among the year’s very finest singles.

If she’s trying to show how grown up she is by how lewdly she can act, she’s not doing a very good job of it.

At the same time, conventional wisdom suggests that rubbing foam fingers in places foam fingers ought not go doesn’t help her credibility as a singer of serious fare like Wrecking Ball.

Perhaps, as proposed by Elton John — who, like Cyrus, played this weekend’s iHeartRadio Music Festival in Las Vegas — she’s a “meltdown waiting to happen.” Frankly, it’s hard to tell.

What’s great about Miley Cyrus, though, is that she’s so funny. She has a weird and finely tuned sense of humor, which she displayed Saturday during two performances at the festival, particularly her afternoon set at the Music Festival Village.

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Dressed in a white hot-pants suit with laces that went flying every time she swiveled her hips toward the audience, Cyrus performed We Can’t Stop and Party in the U.S.A. while surrounded by dancers wearing inflatable mushrooms and rainbows, as well as twerking little people.

With all Cyrus’ activity the past few weeks — her performance at the MTV Video Music Awards, appearing naked in her Wrecking Ball video, breaking up with Liam Hemsworth — she’s shown an uncanny ability to astonish.

But Cyrus could hardly have come up with anything more flat-out flabbergasting Saturday than one of her song choices — Look What They’ve Done to My Song, Ma.

Written by Melanie Safka of Brand New Key fame, Look What They’ve Done to My Song, Ma was a modest hit in 1970 for the New Seekers (and, later, a Quaker Oats jingle).

Though it was a fairly familiar song in the ’70s, covered by Ray Charles, country singer Billie Joe Spears and others, it was never a particularly big hit. It’s certainly not the sort of song anyone would expect a 20-year-old like Cyrus to know.

Its lyrics, though, are particularly relevant to someone who finds herself besieged by the media at exactly the time she’s presenting the music she hopes will define her as a young adult artist:

Look what they’ve done to my brain, Ma

Look what they’ve done to my brain

Yeah, they picked it like a chicken bone, and they think I’m half insane, Ma

Look what they’ve done to my brain

Cyrus’ performance was a bizarre, funny pop-culture moment, for sure, but it also showed the singer revealing herself to critics of an older generation by using one of their own songs, a markedly mature move for a young woman who seldom receives the benefit of that doubt.

And then there was Wrecking Ball. Cyrus performed the song in front of a concert audience for the first time Saturday afternoon, and then again that night.

The afternoon performance moved her to tears. When she finished singing, she had mascara running down her face.

The weird thing about Wrecking Ball is that all the nuttiness of Cyrus’ public persona doesn’t diminish the song.

If anything, the controversy, the bizarre faces, the fear for her mental stability, whatever you want to call it, actually enhances the emotional impact of her performance — the same way country singers often use a cornball novelty to set up a real heartbreaker.

It’s entirely possible that Cyrus’ recent bizarre antics are all a setup. Yes, it’s a way to create attention, but not solely for attention’s sake. Cyrus may have a longer game in mind.

Think of Cyrus as a cute, young, female Andy Kaufman, and the confusing pieces of her recent behavior start to make sense.

Despite all his other issues, the late comedian understood how to generate heat by turning people against him, a principle he learned from watching professional wrestlers.

And, really, how surprised would anyone be to see Cyrus show up some week on WWE’s Monday Night Raw? All her post-VMAs talk about being “messed up” or “an adult acting like a kid” has the feel of a cerebral wrestling villain cutting promos. She’s turning “heel.”

Why in the world would she do that? Any wrestler can tell you that the more people hate you as a heel, the more they love you when you become a “face,” or a good guy, again.

Come to think of it, Madonna could probably tell you a thing or two about that, as well. If Cyrus is stringing her haters along, Kaufman-style, it’s a brilliant, well-played joke.

Don’t want to give Cyrus credit for being that smart? Fine. Maybe she hasn’t consciously set her course. Just remember, though: All her life she’s had the example and advice of a father who was a one-hit-wonder country singer and also smarter than a lot of people thought.

Billy Ray Cyrus may not approve of every creative choice she makes, but he’s there to give her guidance and support whenever she wants it.

Besides, anybody who has the good sense to cut Wrecking Ball and the ability to deliver it like Cyrus does can’t be that stupid.