Rep. Joe Kennedy III (D-MA) delivered a passionate response to President Donald Trump’s State of the Union address on Tuesday night, laying out the Democratic Party’s vision for America.

“We choose the living wage, paid leave and affordable child care your family needs to survive,” Kennedy said. “We choose pensions that are solvent, trade pacts that are fair, roads and bridges that won’t rust away, and good education you can afford. We choose a health care system that offers mercy, whether you suffer from cancer or depression or addiction.”

He gave nods to the #MeToo movements and Black Lives Matter. Importantly, he took on Trump — but also the broader Republican agenda.

“They’re turning life into a zero sum game for one to win, another must lose,” he said.” Where we can guarantee America’s safety if we slash our safety net. Where we can extend health care in Mississippi if we gut it in Massachusetts. We can cut taxes for corporations today if we raise them on families tomorrow.”

He ended by referencing Trump’s notorious name calling.

“Bullies may land a punch. They may leave a mark,” he said near the conclusion. “But they have never, not once in the history of our United States managed to match the strength and spirit of a people united in defense of their future.”

Who is Rep. Joe Kennedy?

The 37-year-old Massachusetts Congress member hails from the outskirts of Boston. He’s the grandson of the late Robert F. Kennedy, the brother of President John F. Kennedy. Robert Kennedy served as senator for New York and was running for president in 1968 when he was assassinated.

Despite his famous last name, Joe Kennedy has flown under the radar since he was elected to Congress in 2012. He has not sought the spotlight or made waves trying to shake up the Massachusetts political scene.

He’s told reporters he’s interested in pursuing a spot in the Senate in the future, though he hasn’t made any moves to challenge Massachusetts’s popular current Democratic senators, Elizabeth Warren and Ed Markey. Nor has he given any indication that he’s thinking of running for governor against the state’s Republican governor, Charlie Baker, a popular moderate.

But he has started to draw more political attention this year as he’s criticized Trump and the Republican Party.

Some of Kennedy’s speeches went viral; one video of Kennedy criticizing Speaker Ryan during the battle to repeal Obamacare drew more than 10 million views on Facebook. Video of another speech by Kennedy on the racial violence and rhetoric after the Charlottesville protests was also watched millions of times.

There is no mercy in a system that makes health care a luxury. GOP repeal bill is not act of mercy. It is an act of malice. #ProtectOurCare pic.twitter.com/2pZG6uqgtl — Rep. Joe Kennedy III (@RepJoeKennedy) March 8, 2017

Democrats are trying to get some of this excitement into the response to Trump this year. The choice of a young Congress member from a famously liberal state of Massachusetts is a notable departure from the party’s choice to respond to Trump’s speech last year: former Kentucky Gov. Steve Beshear, who appealed to the president to keep the Affordable Care Act while sitting in a diner, surrounded by fellow Kentuckians.

Kennedy is certainly young and energetic, but he is also a white man who hails from America’s foremost political family. That’s a contrast to the GOP’s last pick for a SOTU response, then-South Carolina Gov. Nikki Haley, now Trump’s ambassador to the United Nations. A young Indian-American Republican politician, Haley was seen as boosting the GOP’s diversity when she delivered the Republican response to then-President Barack Obama in 2016.

What is the SOTU response, and why is it so difficult to do well?

The origins of the State of the Union response date back to the late 1700s. Presidents George Washington and John Adams would go to Congress to deliver their “annual message,” as it was then called. “In response,” writes Gerhard Casper, “members of Congress traveled to the President’s House, where they gave a formal answer to the issues raised by the President’s address.”

With political parties still forming, this early response was an institutional one from Congress to the president, rather than an effort of the major party that doesn’t control the presidency. But after Thomas Jefferson started giving the annual message only in writing — a tradition that stuck for 112 years — the congressional response fell by the wayside.

By the mid-20th century, presidents were delivering the State of the Union orally again — and with the rise of radio and television, their messages were spread more widely than ever. With partisan competition entrenched, the opposition wanted to have a say. So in January 1966, the GOP congressional leaders — Sen. Everett Dirksen and Rep. Gerald Ford — decided to deliver a response to President Lyndon Johnson’s address. (Dirksen acknowledged the awkwardness, saying that “the President has a mandate under the Constitution” to give information on the State of the Union to Congress, but “we have no such mandate.”)

One thing that hasn’t changed is that State of the Union responses are practically never memorable — for anything good, at least. And there are a few reasons why.

First, the State of the Union address is a very tough act to follow. The president speaks in the Capitol before nearly every high-ranking member of all three branches of the federal government and is frequently interrupted by applause from hundreds of people.

The response has been given in various different settings, but it’s invariably much less impressive. Some responses have been delivered by a politician alone onscreen, speaking to the camera without applause. Govs. Christie Whitman of New Jersey and Bob McDonnell of Virginia gave their responses in their state capitol buildings, in front of applauding crowds. But generally, these can’t compare to the grandeur of the president’s setting.

Second, the president promotes himself and his priorities — but the person giving the response has to represent an entire party. So the response usually tends to stick to the bland, the vague, and the uncontroversial — the party’s extensively poll-tested message, rather than anything particularly new or interesting.

The third problem was described well by Jonathan Bernstein, who asks, “Who wants to watch a second political speech right after one that usually goes on too long?”

So it’s clear that the deck is stacked against the respondent. But total failure isn’t inevitable. In comparison to Rubio’s 2013 debacle, 2014’s response from Rep. Cathy McMorris Rodgers can be deemed a success — because no one remembers it. (These things have to be graded on a curve, after all.)

As for Joe Kennedy, he gave an impassioned rebuttal to Trump Tuesday night. As Vox’s Dylan Scott wrote:

Where Trump painted a dangerous world haunted by Islamic terrorists, Latino gangs and and an unstable North Korea, Kennedy talked about dignity and sought a stark contrast with the current administration.

And Democrats gave him good reviews.