AS AMERICAN politics remains acrimoniously divided, sometimes pop culture can help restore civility.

By any measure, the NBC sitcom Will & Grace, which ran from 1998 to 2006, was a creative and commercial hit. Telling the story of New York lawyer Will Truman (Eric McCormack) and his interior-designer best friend, Grace Adler (Debra Messing), the show's greatest achievement, perhaps, was its straightforward depiction of its lead character's sexuality.

As one of the great sitcoms of the modern era, Will & Grace has increasingly become distinguished for its what's-the-big-deal attitude to positioning the show's main character as gay.

The impact of Will & Grace can hardly be overstated. US Vice-President Joe Biden cited the show as helping America grow more tolerant when he came out in favour of gay marriage in May.

For Messing, it was a satisfying moment.

''We had no idea what the show would become,'' she says. ''But even by the second season, we were contacted by so many people expressing deep gratitude for being represented on prime-time TV.''

Soon enough, it became clear the show was not merely about making people laugh.

''We realised it was meaningful and could perhaps open up dialogues,'' Messing says. ''When Joe Biden referenced [the show] the way he did, it was maybe the proudest moment of my life, besides the birth of my son.''

Six years after the show's cancellation, Messing, 44, finds herself again at the forefront of pop culture. This time, rather than breaking down prejudices, she is merely tasked with helping save America's most venerable TV network.

Messing joins Anjelica Huston as the two most notable names in Smash, a high-budget, high-concept, high-profile drama detailing the making of a Broadway show about Marilyn Monroe.

In the US, Smash was given the most extensive and expansive promotional campaign of any network show. NBC, comfortably defeated by its rivals for years, was desperate for a hit.

It also coincided with the beginning of new NBC president Bob Greenblatt's tenure. He was previously head of Showtime (home to Homeland and Dexter) and he had developed Smash there with Steven Spielberg.

''The producers had been working on it for years,'' Messing says. ''The pilot script was incredible. When Bob left Showtime, we didn't know what would happen, so we waited a couple of months and, finally, he announced he was taking Smash.''

Moving Smash from Showtime to NBC meant some compromises were in order: it would be less edgy, the season would be longer and the budget higher.

''The show's whole landscape changed,'' says Messing, who was the first actor cast. ''I've been open about my desire to keep my personal and professional life balanced. I have an eight-year-old son and I want to be as involved as possible in his life. I was very conflicted about this. But they did a great job scheduling so I could be at school for my son's plays.''

Spielberg was clearly hands-on in the show's excellent pilot, which screened on Foxtel earlier in the year and airs on Channel Seven next week.

''He was incredibly involved in the show's development,'' Messing says. ''It was his baby, his idea. During the pilot, he actually had a camera placed on set that would let him watch everything that was being done here in New York from his LA office. He would give notes and adjustments from there.''

This season tells the tale of the musical Marilyn and the two actors aspiring for the role of Monroe. Messing's character is a Broadway veteran who is also a co-writer of the musical.

As the season progressed, US critics grew restless with Smash's soapy segues from the Broadway storyline. Did that criticism affect the production?

''I like to keep that talk at arm's length,'' Messing says. ''It can distract your focus. But I'm sure the writers and producers were aware and more reactive to what was being said.''

Messing and the cast are filming season two. Tellingly, four of the show's key cast members have departed, as has executive producer Theresa Rebeck.

''I'm someone who doesn't love change in general,'' Messing says, carefully. ''I picked up my whole life and moved from Los Angeles, so I was already traumatised trying to get used to living in New York, navigating the city as a mother and working on a new show. So when all those changes happened, it felt chaotic.

''But because the decisions were made so quickly, it decreased the level of anxiety. Not knowing what's going to happen is the scariest thing. Everybody involved in the creative trajectory of the show is now very excited.''

For Messing, the second season will also mark a mini-reunion. Sean Hayes, so memorable as Jack McFarland in Will & Grace, will join Smash.

''I made them promise that we would be able to act together and do scenes together,'' she says. ''I'm giddy about that happening.''

Smash begins on Tuesday at 9.30pm on Channel Seven.