Walking through the crowd at Hillary Clinton's presidential campaign kickoff last month in New York, I ran into someone I hadn't expected to see. There under a canopy of trees on Roosevelt Island stood a familiar face. The Twitter bird on his T-shirt confirmed his identity. It was DeRay McKesson, a leading activist in the Black Lives Matter movement.

We had never met before, but I immediately recognized the face that had become so ubiquitous in social and mainstream media. He was scrolling through tweets on his cell phone when I approached. "You're everywhere," I told him.

We had seen each other once before last August in Ferguson, before we knew of each other's identities. Since that time, McKesson had set up a base camp in St. Louis and stayed busy traveling the country, chronicling and curating the movement from Cleveland to Baltimore to McKinney, Texas.

But why was he in New York City? He was an observer, he told me, who had come to hear what Clinton had to say. Similarly, I was covering the event for BET, I told him. We had a brief conversation and took a selfie, which I posted on Twitter with his permission. By the end of the hour, I had gotten a glimpse into the sometimes snarky world of online cynicism and critique that follows DeRay's every public move.

"I hope [DeRay] is protesting [Hillary] because her husband is partly responsible for the largest drop in the median wealth of Black households in a generation," one angry Tweeter responded. "Black Americans putting support behind this clown, who is a puppet," another replied. Others attacked Hillary Clinton as a liar who had never done anything for the Black community.

All these responses came from a simple post of a photo. And neither of us was attending the event to endorse or support Clinton. DeRay even posted a critique of her speech after she finished. "So, Hillary Clinton's speech has ended. I heard a lot of things. And nothing directly about Black folk. Coded language won't cut it," he wrote.

With 173,000 followers on Twitter, the 29-year-old activist draws plenty of attention, especially from critics who often see him as a divisive "outside agitator." Just a few weeks ago, some critics even dug up White House visitor logs to prove that DeRay had entered the building three times back in 2011.

Former TV talk show host Montel Williams even complained on Twitter last month that "DeRay is no MLK," which, by the way, is something he never claimed to be. But DeRay's dignified response caught my attention: "And you're no Oprah," he tweeted back to Montel, "and you don't have to be, as I appreciate your work for what it is. Fighting for you too, Montel."

DeRay has now become such a provocative figure that critics created a hashtag, #GoHomeDeRay, that started trending shortly after he arrived in Charleston following the massacre at the Emanuel AME Church last month. What other young Black man provokes such harsh national condemnation merely for attending a church service?

Oddly enough, DeRay sat next to Republican presidential candidate Rick Santorum during the church service, and although Santorum had refused to take a position on the racist Confederate flag in South Carolina, there was no #GoHomeSantorum hashtag trending on Twitter that day to condemn an opportunistic politician.

But despite all the threats and attacks he faces, DeRay does not come across as an angry, bitter militant. Instead, I found a humble, soft-spoken optimist when we met for a breakfast interview in New York's Upper West Side last month.

Dressed casually in a plain white T-shirt and his slightly tattered trademark blue vest, DeRay pushed aside the uneaten melon pieces in his bowl and looked up from the messages on his cell phone. "I'm excited for when we win," he announced.

"What does winning look like?" I asked. The movement has largely succeeded, DeRay told me, in convincing people and exposing the problem, but the next step is doing something about it. Here, the former math teacher and school administrator spoke with the precision one might expect from an academic. "The strategies we used to convince people of the problem will be different from the strategies we need to solve the problem," he said.

"We can actually live in a world where the police don't kill people. That is a real and tangible goal," DeRay said. "And what does it mean to end racism," he continued, "to figure out culturally and structurally how to end racism? If those are what we posit the goals to be, then how do we get there?"

"We won't undo 400 years of oppression in 300 days," DeRay acknowledged. "But what can we accomplish in your lifetime?" I asked. "I think that we can definitely get to zero on police killings," he said. "And I think we can take a huge dent in racism."

It was the same hopeful message one might expect from the man who sleeps with his phone and stays up late to send out the same tweet to his followers almost every night. "Sleep well, y'all. Remember to dream."

Keith Boykin is a New York Times best-selling author and former White House aide to President Clinton. He attended Harvard Law School with President Barack Obama and currently serves as a TV political commentator. He writes commentary for BET.com each week.

The opinions expressed here do not necessarily reflect those of BET Networks.

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