Second gentleman Doug Emhoff's role as a leader confronting antisemitism -- and, personally, his historic role as the first Jewish spouse of a president or vice president -- has taken new significance this week.

"We witnessed a mass murder of innocent civilians," Emhoff told Jewish leaders Wednesday at the White House, slamming his hand on the lectern as he described images of rockets falling, children sheltering from bullets and bodies lining Israeli streets after the attacks by Hamas.

"Many of us feel a deep fear that these attacks will unfortunately -- and already have -- led to a rise in antisemitism. We're already seeing it," he said.

The attacks on Israel by Hamas over the weekend shocked the world and sent ripples through the Biden administration. Amid concerns about rising antisemitism in the wake of the attacks, Emhoff -- one of the White House's most effective messengers on the issue -- has stepped up his efforts to speak out and appears set to become a key face of the administration's engagement with the Jewish community. Internal discussions about Emhoff's plans to meet with the Jewish community in the coming days and weeks are ongoing, a source familiar with planning told CNN.

The attacks in Israel come after the Anti-Defamation League Center on Extremism, which has tracked incidents of US antisemitic harassment, vandalism and assault since 1979, found 3,697 antisemitic incidents in the US in 2022, up a significant 36% from the previous year -- and the highest on record.

Amid that backdrop, the roundtable -- and Emhoff's presence at it -- held special significance for the leaders gathered at the White House. Eighty years ago this month, 400 rabbis from across the country marched to the White House, seeking a meeting with President Franklin Delano Roosevelt, where they hoped to make an appeal to the president to rescue the Jews persecuted in Europe.

"They were refused a meeting with President Roosevelt. They were refused entry to the White House," Nathan Diament, the executive director for public policy at Orthodox Union, told President Joe Biden, Emhoff, and other senior administration officials.

"The fact that we are here today," Diament said in the Eisenhower Executive Office Building, "shows what a dramatic distance we've traveled in these United States."

Emhoff finds his voice as second gentleman

There is no manual for being the spouse of a vice president, but the largely ceremonial role -- one that is unelected -- comes with an automatic global platform.

"There's no playbook, there's no job description, there's, quite frankly, no salary. But what there is, is a way to message and an audience that is sort of ready-made to hear what it is you have to say. ... And in that sense, what feels like a sort of in impotent administration position suddenly feels very important and very powerful," said Kate Bennett, a former CNN White House reporter who extensively covered first and second families.

Sometimes the role is one of a pinch-hitter -- stepping in to lead a delegation on behalf of the president or vice president, to attend an inauguration or perhaps a sporting event. But since his wife took office, Emhoff has crafted a deliberate and timely two-pronged portfolio: advocating for gender equity, and, unexpectedly, fighting antisemitism.

Emhoff has held multiple roundtables, met with students, lit the menorah and affixed a mezuzah outside the vice presidential residence. Earlier this year, he traveled to key sites in Poland and Germany to mark International Holocaust Remembrance Day and meet with special envoys and coordinators on combating antisemitism alongside US Special Envoy to Monitor and Combat Antisemitism Ambassador Deborah Lipstadt. And in May, the Biden administration unveiled the first-ever national strategy to combat antisemitism.

The efforts first intensified last year. Emhoff was "infuriated" when, after rapper Kanye West posted a number of incendiary antisemitic tweets, someone hung a banner over Interstate 405 near his home in Los Angeles that said, "Kanye was right."

"It just infuriated me. ... And that was one of the other reasons why I leaned so hard into the plan and the meetings and all the speaking and writing I've done -- because it's everywhere, including my neighborhood. And I have to do more. I have this microphone. I have this incredible platform, once in a lifetime opportunity to actually do something about it," he said during a Yom Kippur conversation at Adas Israel Congregation in late September.

The rising tide of antisemitism, Emhoff said, is directly tied to threats to democracy -- something Biden staked his 2020, and now 2024, campaigns on.

"We really are facing an unprecedented attack on our democracy, which is fueled by hate. And that's what it is. So, in order to preserve our democracy and live the way we all want to live, we've got to deal with this issue. ... It's all interrelated and that's the way we have to approach it," Emhoff said last month.

As he navigates a role inside the administration yet outside policymaking, Emhoff's capacity to build coalitions could be a key tool.

Rabbis Aaron Alexander and Lauren Holtzblatt, who were one of the second gentleman's first calls before he moved to Washington, told CNN in a joint interview that Emhoff can use his position to foster interfaith coalitions and relationships that will be critical in the coming weeks and months.

"As the second gentleman, as an American, any place in which he's going to and meeting with people of faith as an open and proud Jew is good -- feels like it's good for the Jewish people. And it's good for America because those relationships matter right now," Alexander said.

"To the extent that the second gentleman is an influential figure in helping create those partnerships, and to foster them, with significant leaders and other faiths who have influence over their people as well, it feels meaningful," he said.

'I take it very seriously'

And the role also conveys influence within the administration.

"People in positions of leadership and influence bring their personal experiences and their personal identities into those roles. And you know, the fact that Doug Emhoff is the first American Jew who is in one of these roles, and the fact that he takes his Judaism seriously and that he's embraced his role in that way, even before this terrible war broke out, gives it an added dimension of seriousness and attention in the halls of the White House," Orthodox Union's Diament told CNN in an interview after Wednesday's discussion.

While Emhoff has said it's not what he "expected to be doing" as second gentleman, he views his role amplifying the strategy to combat antisemitism as one of "responsibility" and "accountability."

"I take it very seriously," he said during the Yom Kippur conversation.

And the antisemitism strategy, Amy Spitalnick, CEO of the Jewish Council for Public Affairs, who was present at Wednesday's meeting, is "all the more crucial" in the context of Israel's war with Hamas.

"We can't let this crisis derail all of the progress we've made and undercut the urgency of this broader effort to protect not just the Jewish community, but so many communities under threat right now," Spitalnick said.

Emhoff, she added, has played a "deeply important" role in the administration's response.

"He is conveying a lot of the pain and frustration and anger many of us are feeling in this moment. It's clearly personal to him," she said. "The reality right now has conspired to make it more urgent -- and he has really embraced that."

One of Emhoff's most important messages to Jewish Americans, he said on Yom Kippur, is to take pride in the faith.

"Be proud you're Jewish. And have joy in it, and just live openly and proudly. ... I love it. I think it's the best thing ever, and everyone needs to have that same pride," he said.

Using his platform to share that message in this moment, Holtzblatt said, "is essential."