Michael Ian Black has bailed on us.

The comedian, author, actor and all-around, self-described very famous celebrity got himself a role as a “douchey office worker” in Paul Rudd and Amy Poehler’s new film, “They Came Together.”

Black was supposed to be in Washington today with co-author Meghan McCain to publicize their new book, “America, You Sexy Bitch.” But the movies call. Alas.

The book follows the liberal comedian and the conservative blogger across the United States during the summer of 2011 — a chronicle of their relationship as they go from politically opposed strangers to politically opposed friends.

HOH spoke with Black on Wednesday after he had spent some time signing copies of the book in New York’s Bryant Park.

The book was his idea, while he was, like many other Americans, unemployed. “The process goes like this. I don’t know what I’m doing with myself. I take an Ambien. I see that Meghan’s on Twitter. I tweet at her, ‘Do you want to write a book together?’

“There wasn’t much more thought then that,” Black says. “Other than, ‘Should I finish this bag of Tostitos now and then tweet Meghan?’ Or, ‘Should I tweet Meghan and then finish the bag of Tostitos?”

He does concede that he has been interested in politics for a long time — since his late 20s at least.

“When I really started wondering why I even identify as a Democrat — I just always did because I was brought up that way — but I never spent any time examining what that meant to me, what I thought the government should do and what I thought I should do for the government.”

Around that time, he started listening to a lot of conservative talk radio, Black says.

“Which made me much more sure of my beliefs as a Democrat then anything else possibly could have done,” he says.

At the same time, Black says that he felt as if no one was talking about politics the way he wanted to talk about politics, which was to ask basic questions and listen for the answer. “I wanted to hear what people had to say. I didn’t want to play a blame game or convince people of anything.

“I just wanted to have a conversation, because I feel like a conversation isn’t really happening,” he says. “I feel like people are talking at each other and past each other. People aren’t talking to each other, so I thought maybe I could talk to Meghan.”

According to Black, the reaction from the book has been interesting.

“It’s been rather polarizing. People who are in politics, particularly Republicans, seem to really hate it,” he says. “A lot of them, especially Republicans, have a grudge against Meghan. They really hate her.

“When she does stuff, they just sort of reflexively don’t like it, but, I think both of us are fine with that, because the readers — people who have bought and read the book — really seem to be embracing [the book], and we really wrote it for people who are not so invested in politics.”

So, why then, of all the conservative bloggers and Senatorial daughters out there, did Black, in an Ambien haze, turn to McCain.

“On the surface,” he says. “We don’t have much in common, but I’ve been a fan of hers for a long time. [She’s] someone who lays it out there. What she believes and consequences be damned. I like that. I admire that. It’s hard to be a comedian and not admire that.

“I felt like she was the kind of Republican I could hang out with, and get along with and have a good time with,” Black says. “I love her. I really do. She is both a hoot and a holler.

“If I was surprised about anything [by the end of the road trip], it was how much I came to care about Meghan and how much I feel like I understood her. For me, it was as much a personal journey as it was political journey,” he says. “It was as much a story of a friendship emerging out of bizarre circumstances.”

Black’s mother and father divorced when he was young, mostly, he says, because of his mother’s lesbianism. She’s currently living in Florida with her partner, but it might explain a little of the actor’s vehemence when discussing LGBT issues in the book and in person.

“She has had a marriage ceremony with her partner. It’s obviously not recognized by the state,” he tells us.

“Any proponent of gay marriage must feel maddened and bewildered as to why this is even an issue, as to why this should cause anyone any agitation,” he says. “All the push back is from religious organizations and, in my opinion, the government has no business addressing those concerns.”

There is no proponent of gay marriage that says the state has to recognize gay marriage and so does your church, Black insists, sounding slightly exasperated

Towards the end of “America, You Sexy Bitch,” McCain and Black finally arrive in D.C. In one vignette, the duo meets with the Log Cabin Republicans at a bar in Dupont Circle. In the book, Black wonders if the out-of-the-way nature of the bar and staid ambiance signal a certain level of shame or even self-loathing.

“From the outside, it’s hard to look at a gay advocacy group in the Republican Party and not feel like there has to be something going on there,” the actor explains when asked about the passage. “The GOP is so stridently anti-gay that I don’t know how you can identify with that party no matter what your politics are, because ultimately, to me, it would feel like my party rejects a fundamental aspect of who I am.

“So even if I am a military proponent and a small-government proponent and a ‘cut the capital gains tax’ proponent and everything else, I personally would have a very hard time overcoming that [part of the platform].”

However, he does admire their loyalty.

“[T]he fact that they are able to say, ‘Look, this is one aspect of the platform we don’t agree with, so we’re fighting to change it from the inside,'” he says.

Still, he does think that the Log Cabin Republicans are changing the GOP.

“Any change that’s happening in the Republican Party and elsewhere in terms of that specific issue is changing despite the Republican Party and work the Log Cabin Republicans are doing, not because of it.”

Black likes the group, though.

“I thought [the Log Cabins] were great people. We had a great time. We had a great conversation, but, you know, I don’t know that they are moving the football forward for their own cause. I really don’t. I hope they are.”

Pushing this book about American politics has turned Black into something of a reluctant pundit.

“I feel like such a phony,” he says. “Because, people ask me political questions. I’m falling into the same trap as a lot of people do, which is: ‘Who am I to have an opinion?’

“But, the fact is,” he continues. “I have to own that I wrote this political book, and I have to own that I should have an opinion and that we all should have opinions and that we shouldn’t be afraid to express them without fear of ridicule. It’s been hard to embrace that. It has been hard to just say what I think and why I think it and not feel apologetic for having an opinion.”

In some way, Black seems to have fallen for the deliciously fun parts of politics, which at its heart is a world of outsized characters struggling for power and to change the world.

“Oh, yeah. There’s no doubt. Being in politics, you have to be kind of a freak,” Black agrees.

There is some overlap between acting and politics, however. The two fields are replete with monster egos and buckets of sensitivities. Still, actors have the luxury of breaking away.

“[My] sense about politicians is that they’re bigger actors than actors. Many of them have to pretend to be something they’re not. Actors — you turn on the cameras and you pretend to be something you’re not, and then you turn them off. You don’t have to be that person anymore, but politicians have to live that life all the time.”

You can grab your copy of “America, You Sexy Bitch” pretty much anywhere now. Head over to the DC JCC tonight to hear McCain’s version of her political road trip with Black.