Joe Biden-Hunter Biden photo is a teachable moment on fathers and masculinity

President Donald Trump and his allies have tried a series of increasingly desperate tactics to derail former Vice President Joe Biden's campaign momentum. As these would-be October surprises fall flat, Trump surrogates appear to have reverted to the oldest tool in their political arsenal: attacking Biden's masculinity.

On Wednesday, John Cardillo, a host on Newsmax, a Trump-aligned media network, tweeted out a photo of Biden holding his son Hunter and kissing him on the cheek. "Does this look like an appropriate father/son interaction to you?" Cardillo asked.

While Cardillo isn't an official Trump surrogate, his attacks are very much in line with Trump's incessant bullying of his opponent's masculinity. From mocking him for the size of his masks to simply calling him physically weak, Trump hasn't been subtle. Many male voters have taken notice. Because like many other institutions in America, fatherhood is changing. Men want to be able to express their love for other men, especially their sons. And they want to be able to do this without being called weak. To deny them this ability isn't just old-fashioned; it perpetuates a toxic societal cycle that can have dangerous consequences for young men and boys.

Biden hasn't bought into these stereotypes, either. "What is this macho thing, 'I'm not going to wear a mask'?" he said at a recent town hall. "What's the deal here? Big deal! Does it hurt you? Be patriotic, for God's sake." Shortly after, a pro-Trump Fox News contributor responded: "Might as well carry a purse with that mask, Joe."

Make no mistake: The presidential election will be a referendum on masculinity. And there is no better example of the contrasting attitudes of these two men than their behavior as fathers. While Trump believes that men who change their children's diapers are "acting like the wife," Biden took on every single one of his first wife's responsibilities (and far more) when she suddenly died in a car accident along their daughter. While Trump is known for reportedly calling his son dumb, Biden publicly lauded his son Beau — calling him a better politician than he could ever be — after Beau passed away from brain cancer.

Even when Trump tried to rattle Biden during the first presidential debate by calling his son Hunter a cocaine addict, Biden's unconditional and warm paternal response turned one of the ugliest moments in presidential debate history into a heartwarming one. "My son, like a lot of people ... had a drug problem," Biden said. "He's fixed it. He's worked on it. And I'm proud of him. I'm proud of my son."

But perhaps nothing else typifies Trump's questionable approach to fatherhood more than the way he treats his daughters. From openly flirting with and inappropriately touching his grown daughter Ivanka or speculating about the future breast size of his daughter Tiffany when she was but a toddler, Trump has objectified his children in strange and sometimes creepy ways. And Trump doesn't just want to talk about his daughters' bodies — he wants to take credit for them. When Ivanka was only 22, Trump told Howard Stern that she had "got the best body," and he bragged about the money she made modeling. "You know who's one of the great beauties of the world, according to everybody? And I helped create her. Ivanka." No wonder Ivanka Trump left fathers out of her parental leave policy proposal in 2016. It's not clear she ever had one.

While we have always expected moms to be nurturing and physically affectionate, we're beginning to expect the same kind of emotional involvement and empathetic parenting from men. Fathers are still more likely to sing to their daughters and roughhouse with their sons, but all of this is changing rapidly. According to the Pew Research Center, fathers are spending far more time with their kids than in 1965. Fathers are also much more likely than mothers to report feeling like they don't see their kids enough. Men are growing up to become very different from their own fathers. A study by Dove Men+Care in 2015 suggested that the vast majority of men (86 percent, to be exact) believe masculinity means something different to them from what it meant to their fathers. But only 7 percent of the men surveyed said the guys they see on TV and in movies reflect their own attitudes toward masculinity.

A lot of guys are yearning for permission to connect with others — male and female.

I've spent the past few years speaking to men around the country. And what I've learned is that a lot of guys are yearning for permission to connect with others — male and female — and are eager for a gender revolution that sets them free to reveal vulnerability, affection and intimacy without their manhood's being scrutinized or questioned.

I want to live in a world where boys are hugged more, not less. Especially during one of the darkest years in this nation's history. America needs a big warm hug and — and it needs a president man enough to do it.