Dean Obeidallah, a former attorney, is the host of SiriusXM radio's daily program "The Dean Obeidallah Show" and a columnist for The Daily Beast. Follow him @deanofcomedy . The opinions expressed in this commentary are his.

(CNN) By inviting "alt right" (aka white supremacist) darling Milo Yiannopoulos (known as "Milo") onto his HBO show Friday night, Bill Maher could've seized a great opportunity to expose Yiannopoulos' history of hate. After all, Yiannopoulos has spewed so much toxic garbage that he was permanently banned by Twitter in 2016 , which says a lot, considering the cesspool that swirls on that platform.

So when Maher faced Yiannopoulos on Friday, did the HBO host press him on his view that college rape culture is a fiction and that women are often lying when they report being raped? Did Maher ask him about his anti-Semitic comment that "Jews run the media," or did he ask why Yiannopoulos wore a Nazi Iron Cross when he was younger? Did Maher press him on his demonization of transgender people as, in essence, sexual predators?

No. Instead Maher actually bonded with the extremist author and lecturer on their shared anti-Muslim views. Yiannopoulos complimented Maher: "You're sound on Islam unlike most people on your show." To which Maher glowingly responded, "Yes, that's true." (Although when Maher remarked that all religions were "stupid and dangerous," Yiannopoulos pushed back noting that, as a Catholic, he thinks his own faith is great.)

You know, there's nothing nicer than seeing two people who appear to be on different ends of the political spectrum bond over how much they dislike Islam, right? And no question: Maher and Yiannopoulos do indeed appear to be in lockstep when it comes to Muslims. Yiannopoulos, writing that "America has a Muslim problem" has conflated all Muslims with ISIS and has even defended loathing of Muslims with the comment, "fear of Islam is entirely rational."

Maher has echoed that very sentiment with his own comment about Islam that, "The more you know, the more you would be afraid." And Maher was even praised by the alt-right Breitbart, where Yiannopoulos works as editor, for his remark in 2015, "I think that Islam is a problem."

On his show Friday, Maher did gently push back when Yiannopoulos mocked HBO "Girls" star Lena Dunham with his playful response, "Let's not pick on fellow HBO stars." But why didn't Maher at any time passionately challenge Milo?

In fact, stunningly, at the end of the interview, Maher seemed to be doing his best to make Yiannopoulos' hateful views more acceptable. Maher concluded the interview by reading "provocative" jokes the late comedian Joan Rivers had made and saying she was still considered a "national treasure."

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His point appeared to be that if some people gave another comedian a pass, then why shouldn't we do the same with Yiannopoulos? Well, the reasons are obvious: Rivers was actually a comedian, while Yiannopoulos is a political pundit who writes for Bretitbart.com, a website that proudly spouts white-supremacist views and was, until recently, headed by Steve Bannon, who is now a senior adviser to the President of the United States, Donald Trump.

It's especially curious that Maher didn't stand up to Yiannopoulos, given that he had been roundly criticized for even booking him on the show. In fact, Jeremy Scahill, a frequent guest on Maher's show, canceled his appearance for that night because he vehemently disagreed with Maher presenting Yiannopoulos with a national TV platform from which to "legitimize his hateful agenda."

Thankfully, former Comedy Central host Larry Wilmore was on the panel and showed us how you confront hate. In the "Overtime" segment of the show, which can be seen online , Wilmore confronted Yiannopoulos's past racially-tinged attack on African-American SNL cast member Leslie Jones and his hatemongering about transgender Americans.

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In fact, when Yiannopoulos asserted that transgender people are "disproportionately involved" in committing acts of sexual assault -- a lie that has been debunked by experts -- Maher remained quiet. It was Wilmore who stepped up to challenge his "statistics."

And when Yiannopoulos went on to say that being transgender was a "psychiatric disorder," Maher kept his silence, while it was Wilmore who continued to press Yiannopoulos. The discussion between Wilmore and Yiannopoulos escalated until Wilmore told him "you can go f*** yourself," drawing a round of applause from the studio audience -- which had no doubt hoped Maher would've summoned half that much passionate pushback.

If Maher has made a strategic decision to court Yiannopoulos' legion of white-supremacist followers, that's his despicable choice.

But if he truly wants to regain progressive fans and the respect of his peers, then when he invites guests like Yiannopoulos, Maher should passionately press them on their hate, not mainstream it.