Last Sunday, mere hours after a gunman attacked the LGBT club Pulse in Orlando, Florida, leaving 49 people dead and countless others injured, John Oliver appeared on his late-night HBO program Last Week Tonight. There, he paid tribute to the victims in the massacre, and also urged his viewers to remain hopeful, pointing to the long lines of people at Orlando area blood banks as evidence of good triumphing over evil.

This week, after the British comedian and his team had a little more time to research, Oliver addressed the different responses to the tragedy, from presumptive Republican presidential nominee Donald Trump repeating his call for a travel ban on Muslims (despite the fact that the AR-15 wielding shooter, Omar Mateen, was born in a Queens, New York, hospital about 8 miles from where Trump was born), and the Democrats filibustering Congress in order to get a vote on gun reform.

Since the Republicans control the House, however, it’s not likely that any gun control legislation will make it through Congress—much to Oliver’s chagrin.

“Here we are again after another mass shooting with weak legislation due to failure. And there is clearly a disconnect between public opinion, which favors—to varying degrees—a number of different gun control measures, and any practical action in Washington. And it is pretty clear what is standing between those two things: and it is the National Rifle Association,” said Oliver.

“To be fair to the NRA, it’s not surprising they take a hard line on gun control legislation,” he added. “They’re an advocacy group, it’s what they’re supposed to do. What is shocking is just how successful they’ve been at it.”

Indeed, the NRA has not only managed to coax politicians to embrace soft gun laws—294 congressmen have received a total of $3.7 million from the NRA since 1998—but also prevented the Centers for Disease Control (CDC) from even studying the causes of gun violence. Yes, back in 1997 the Dickey Amendment was added to a congressional bill, and it bars the CDC from any research that would “advocate or promote gun control,” effectively blocking CDC research into gun deaths. As a result, the CDC has not been able to produce a comprehensive study on how to prevent gun violence in 15 years.

Since the Dickey Amendment, CDC funding has dropped 96 percent to just $100,000 of last year’s $5.6 billion CDC budget.

Oh, and that’s not all. “It’s not just the CDC struggling to collect reliable gun-related information. For decades, the NRA has successfully lobbied to prevent the ATF to have a database that is electronically searchable by name when tracing the origins of firearms,” said Oliver. That’s right: for gun shops that have gone out of business, people must review paper and microfilm records to trace the ownership of guns, many of which are barely legible. In 2016.

“So how the FUCK has the NRA managed to accomplish all of this? Because the truth is, they’re not that large an organization. They claim they have a membership of around 5 million, but that is three million fewer members than Planet Fitness—and the members of Planet Fitness have almost no power. Most of them don’t even have the power to go to Planet Fitness,” joked Oliver. “The real power of the NRA are in its members who are highly motivated and can be mobilized quickly.”

Yes, the NRA not only contributes a great deal of money to lobbying for guns and against gun control, but they also have very passionate and vocal supporters who fight hard on their gun-loving overlords’ behalf. And they have a simple message: NO to gun control.

“It’s a lot easier to drum up support when you’re just flatly against something,” offered Oliver. “There is a reason that TLC insisted on ‘No Scrubs,’ and not the implementation of a national registry of potential scrubs, aka ‘Bustas,’ that would screen for scrub-like tendencies, or affiliations with known scrubs. They knew ‘No Scrubs’ is a lot catchier.”

Back in 2013, in the wake of the Sandy Hook massacre that claimed the lives of 26 people—including 20 schoolchildren ages 7 and under—a gun control amendment was proposed by Sens. Joe Manchin (D-WV) and Pat Toomey (R-PA) The Manchin-Toomey amendment, as it was called, would have required universal background checks on all commercial sales of guns. Unfortunately, it was shot down by Congress.

“The truth about politics is it’s about showing up. Remember the Manchin-Toomey amendment? Well, a national poll at that time found that 88 percent of people supported universal background checks, and yet Manchin’s office claimed maintains that of the calls they received, they ran 200 to 1 in opposition to the bill, and that’s why it’s actually important to call your congressman,” said Oliver.

Just this past week, Representative Tony Cardenas (D-CA) introduced an amendment to a mental health bill in front of the House Energy and Commerce Committee that would have authorized the Centers for Disease Control to offer grants for gun research. Unfortunately, it was not passed.

“Are you fucking kidding me? That happened four days ago, and I’m guessing that you’re hearing about it for the first time now,” said Oliver. “The Dickey Amendment is emblematic of the chokehold the NRA has over even basic gun data, and it should obviously be overturned, but the hard truth is: NRA members seem to care more consistently about preventing gun control than most of us do about passing it.”

Oliver then called on his viewers to call up their local congressman or congresswoman over and over again—not just in the wake of a mass-shooting—to remind them to appeal the Dickey Amendment. “Repealing it is not asking much. It’s not gun control! It’s enabling us to have an informed conversation about what that could look like,” he said. “And if or when a proposal you like is on the table, you’re going to have to make all those calls again, because remember: it doesn’t take much to outnumber the NRA. Planet Fitness members outnumber them. But it’s time for us to learn what those members haven’t: if you’re going to see serious changes, you actually have to show up every fucking day.”