As they gathered backstage before a concert in Berlin to watch the video, which has now had 75 million views, tears streamed down the faces of her tour family.

“I cried while I was singing it. We were crying on set as we did the video,” she says as her tour bus rolls out of London, heading for the V festival in Chelmsford, Essex.

The first single from Beautiful Trauma, her seventh studio album, had already barrelled to the top of the charts in Australia. And its powerfully emotive video, directed by British filmmaker Georgia Hudson, confirmed the initial impressions this was a protest song, an anthem for those who felt disenfranchised in a world gone mad.

It wasn’t her first pick for the single to reintroduce Alecia Moore, known as P!nk to millions of fans for the past 18 years. It was the last track she wrote for an album she had spent three years working on, penning more than 50 songs.

When she has mixed politics with pop, the Get The Party Started singer hasn’t always been met with universal approval.

Her 2006 song, Dear Mr President, an open letter to then US President George W. Bush protesting his administration’s record on equal rights, poverty and the Iraq war, provoked a firestorm of hate from those who didn’t agree with her social conscience. She was even booed in concert by Bush supporters, who also happened to be P!nk fans while supporting Justin Timberlake on the American leg of his FutureSex/LoveShow tour in 2007.

But every time she played What About Us to anyone, the response was an immediate and emphatic “hell yeah!” And when Willow Hart, the daughter of Alecia Moore and her motocross champion husband Carey Hart, proclaimed it as her favourite, its first single fate was sealed.

“It became her favourite,” P!nk says, pointing at Willow who is playing Monopoly with her dad and nanny.

“It got me thinking. ‘Oh, that’s weird if a six-year-old likes it. That was not what I expected.”

Willows asks her mum why she thought it was weird.

“I don’t know ... it seems to be an older, more serious song, I guess. But it’s not, is it? It just feels good. And every time I heard it, it grew on me and grew on me and grew on me

and grew on me.

“And obviously if your head is not completely in your ass, then you are aware of what’s going on in the world, and it felt more and more like my truth.

“I’m known for bombastic, gimmicky, screamy, obnoxious, heartbroken first singles; So What, Raise Your Glass. And I loved that this wasn’t that. It just felt more true” .

When P!nk completed her 2013 The Truth About Love world tour, after 140 concerts in America, Europe and Australia, she needed time out.

There were two projects on top of her list. The first was a creative one, a duets album with her friend Dallas Green, the Canadian singer songwriter known as City and Colour. Calling themselves You+Me, they released their musical joint venture of acoustically driven folk — including a version of Sade’s No Ordinary Love, in October 2014.

And then P!nk started working on a project with her husband with the working title Baby No.2. Their son Jameson was born last December and his mum isn’t the only one who wants to “eat his face off”. He is one adorable little boy.

While the Harts were trying to procreate, she kept creatively engaged by writing songs for movies.

“I spent a year just writing for movies, just to try it, just to see. Why not?” she says.

“I had never had this kind of time. It was fun writing just to write, without being on a deadline, without expectations.

“So I got to write a lot of different stuff. I kept going, things picked up and then it was ‘OK, here we go.’”

One of her soundtrack submissions proved to a supremely successful stop gap for fans patiently awaiting something new from the Who Knew chart-topper.

Just Like Fire was released as a single from the Alice Through The Looking Glass soundtrack last year and topped the Australian charts on its second week, going on to reach triple platinum here with more than 200,000 copies sold.

Like many of her clips in recent years, her husband and daughter made a cameo in the music video.

She proved to be on a pyromania roll when she returned to the charts a few months later as the featured artist on Setting The World On Fire, a single from American country music star Kenny Chesney. With her assist, it became his highest chart entry in Australia, peaking at No. 26.

And then she returned to the Australian top 20 when she joined with Sia to sing on Waterfall from EDM artist Stargate.

P!nk confirms she wrote several songs with her friend Sia for Beautiful Trauma but none made the cut. It was tough competition; she had 50 songs to choose from, co-written with some of the world’s most famous hitmakers.

Jack Antonoff is the writer and producer she worked with on the title track. Lovers of pop trivia would recognise his name firstly from his days in pop band fun. and then as the sonic architect who helped Lorde and Taylor Swift sculpt their recent musical offerings.

As well as Beautiful Trauma, another hit-in-waiting called Better Life, a commentary inspired by the unreal world of Instagram, was among “the bunch” she created with Antonoff.

“I had worked with Nate from fun for Just Give Me A Reason,” she says.

“I thought Jack and I might have fun together and I was right. I just love his whole thing. He’s this quirky Bruce Springsteen loving rad New Jersey dude. I just love him.

“Did you hear Better Life? That’s another one inspired by Instagram. I want to start an account that is actually the real stuff, how you actually look when you wake up in the morning or when you’re having an argument.

That breastfeeding photo I did the other day … I do post a lot of “I probably shouldn’t have posted that” photos. It looked weird.”

During her years of writing “slow, sad songs” which reminded her of Adele, through to rediscovering her “fun songs’ side and socially conscious affirming anthems — and having a baby — she reconnected with Max Martin, the Swedish producer with the Midas touch who has been crafting the sound of now for the past two decades.

He produced Revenge, one of the album’s “fun” tracks which she also jokes but also hopes will score her a nomination for a Best Rap Grammy.

It features a Grammy-winning rapper whose identity has been much rumoured but will be confirmed when Beautiful Trauma is released on Friday.

P!nk and her team swore everyone who has heard the song to secrecy. And who wants to be the one to spoil a P!nk surprise?

Another of her favourite collaborators was Issues chart slayer Julia Michaels. The 23-year-old emerging pop star already had credits on tracks by Demi Lovato, Fifth Harmony, Selena Gomez, Hailee Steinfeld, Justin Bieber, Rita Ora and Britney Spears before busting out as an artist with her own single.

“She’s so good, so good. She’s really comfortable in her delicateness. She’s very, very talented and her strength is in that delicateness,”’ P!nk says.

“Most people who have that try to hide it, camouflage it a little bit but she is comfortable with it. I found it really easy with her. And she’s just a cool chick, quirky and cool. And a lot is happening for her right now.”

She cites one of her favourite track is Barbies. And no, it’s not an ode to that great Australian cooking tradition.

“I love Barbies, Willow loves Barbies,” she says.

“There were five different versions of this album and I didn’t finalise it until four days ago.

“It was really hard. It’s like leaving out a child, it’s awful. What could I live without for now? I would change it tomorrow.”

P!nk’s Beautiful Trauma tour kicks off at the Perth Arena on July 3 and 4. She will then play the Adelaide Entertainment Centre on July 10 and 11, Melbourne’s Rod Laver Arena on July 16, 17, 19 and 20, Sydney’s Qudos Bank Arena on August 3, 4, 6 and 7 and the Brisbane Entertainment Centre on August 14 and 15.

There will be a pre-sale for Telstra customers from October 16, with general sale on October 20.