Are Democrats willing to stand up for democracy? If it comes down to Democrats in the U.S. Senate, I am not so sure.

As of this writing, more than 65 House Democrats have decided not to attend the inauguration of Republican President-elect Donald J. Trump. The boycott grew quickly after Georgia Democrat and lifelong civil rights leader Rep. John Lewis told NBC’s Chuck Todd that he did not believe Trump was a legitimate president and that he would not attend the inauguration.

Trump soon began berating Lewis on Twitter, calling him “all talk, talk, talk – no action,” and claiming Lewis’ district is “in horrible shape and falling apart.” Lewis has literally put his life on the line many times in the struggle for civil rights and is widely respected in Congress for his leadership, ethics, and honesty. And far from “falling apart,” his highly diverse district of 750,000 people includes several affluent areas of Atlanta and its suburbs. In attacking Lewis, it seems Trump finally went one tweet too far. As of Wednesday, Secretary of State John Kerry had joined members of the House in refusing to attend the inauguration.

Still, two-thirds of the Democratic House Caucus remain silent. And not a single Democratic senator has stepped up to say that they will stand with John Lewis and refuse to attend the inauguration. The reasons run from “tradition” to vague mutterings about the Constitution.

But this is no normal time. And because of this, Democrats must stop adhering to some norms—like attending the inauguration and showing implicit approval—in order to restore respect for all of them and fight for our democracy.

Our democracy is built both on the rule of law and on the tacit acceptance of norms of behavior that form what is otherwise the fragile foundation of our union. Solid respect for the electoral system and for voting rights, a free press, a commitment to putting the country above personal gain and party, and respect for the spirit as well as the letter of the Constitution are among those many norms.

In the past two decades, an increasingly radical Republican party has shown itself also to be increasingly willing to violate these and many other standards of our democracy in a quest to cement its power. As Steven Levitsky and Daniel Ziblatt, both professors of government at Harvard University, wrote in December in the New York Times, “Many Americans … trust our system of constitutional checks and balances” as a bulwark of democracy.

But, they continued:

[T]he institutional safeguards protecting our democracy may be less effective than we think. A well-designed constitution is not enough to ensure a stable democracy …. Democratic institutions must be reinforced by strong informal norms. Like a pickup basketball game without a referee, democracies work best when unwritten rules of the game, known and respected by all players, ensure a minimum of civility and cooperation. Norms serve as the soft guardrails of democracy, preventing political competition from spiraling into a chaotic, no-holds-barred conflict.

One of the most recent signals of the GOP’s disrespect for democratic norms—and for the Constitution—was Senate Majority Leader Mitch McConnell’s (R-KY) refusal to hold hearings and a vote on President Barack Obama’s nomination of Judge Merrick Garland to replace deceased Supreme Court Justice Antonin Scalia. Another of the many signs of disrespect for norms over the past few years were the declarations by both McConnell and then-Speaker of the House John Boehner that the GOP would do everything it could to see him fail, despite the widespread economic and social suffering this caused. Yet another was the willingness of the party to abide and propagate racist attacks on President Obama and on First Lady Michelle Obama.

Donald Trump has taken all of this many steps further. He called for and condoned violence at political rallies. He threatened to jail his then-opponent, former Secretary of State Hillary Clinton. He hired a man known for his affiliation with white nationalists and supremacists as a chief adviser. He praised a foreign leader as being stronger than our own president and called on Russia to hack Clinton’s emails.

Throughout and since the campaign, Trump has belittled, mocked, and suggested jailing and suing members of the press. He has steadfastly refused to submit financial documents to public scrutiny, leaving us with no sense at all of whether and how he might benefit from his role as president, a violation of both norms and law. He has appointed a group of cabinet members characterized by ethical problems, little experience, and hatred of government. He has mocked intelligence agencies and interfered in foreign policy in 140 characters. He lies and misrepresents facts with abandon. And he ran a campaign rife with so much racism, xenophobia, antisemitism, and misogyny that many people are truly afraid for the moment his hand comes off the bible at his swearing in. The abject failure of the GOP to call him out on any of these and other acts underscores how craven that party has become, and how willing they are to abide the “slow erosion of democratic norms.”

This erosion may not be immediately apparent to the public writ large, which makes it all the more critical that Democratic political leaders step up and lead, making clear at every step of the way what is at stake. As Brendan Nyhan, a political science professor at Dartmouth, noted in an interview in December:

What I want to caution people against is the idea that the slow erosion of democratic norms is somehow OK because we haven’t seen [a] dramatic event like a coup. What’s much more likely to happen is a slow erosion of norms … I never thought I would see in my adult lifetime [a] presidential candidate endorsing violence, calling for the leader of the opposition party … to be imprisoned and … calling the results of the election itself into question. Those are all violations of fundamental norms of democracy, even if they’re not inscribed in law, and we should take them seriously as harming our democracy.

While Democrats may now be leading the charge against the repeal of the Affordable Care Act and in vetting nominees for cabinet posts, these are the actions of normal politics in normal times and far from sufficient to confront the crisis at hand. Nyhan noted, as Clare Foran wrote for the Atlantic, “a failure of American institutions to safeguard political norms [during the primary election]. Following the election, [Nyhan] warned that institutions and elites have continued to tolerate illiberal behavior.” This toleration seems to be the continuing pattern of the Democratic Party.

Now is the right and the most urgent time for Democrats to make the case for our democracy. It falls to both the Senate Democrats and the remainder of the House Caucus to draw a stark and immutable line, starting with the inauguration. The time is now to stand up by saying “No.”

No, we will not attend the inauguration, unless all cabinet members go through rigorous background and ethics checks and ample time for hearings on these nominees in the Senate is scheduled.

No, we will not attend the inauguration, unless Donald Trump releases his tax returns.

No, we will not attend the inauguration, unless Donald Trump openly apologizes to Rep. Lewis as well as to all of us for the racist, xenophobic, and misogynistic claims he made repeatedly during the campaign.

No, we will not attend the inauguration, unless Donald Trump makes clear he will not retain a private security force; renounces all forms of violence and discrimination; says he will hold regular press conferences; and promises to ensure access by the press in office and while on travel.

No, we will not attend the inauguration, unless Donald Trump makes clear and transparent efforts to completely divest himself and his family from his company.

No, we will not agree to depriving millions of people of health care, depriving millions of children of good public schools, depriving millions of women of reproductive health care, or depriving millions of their voting rights.

With only two days to go, it is clear that not all of these demands can be met, but by standing up now for these and other democratic norms and principles, the Democrats will have shown that they are going to play hardball from day one in order to preserve and ensure the future of our democracy.

It’s up to you, Democrats. After all, a lot more is at stake than your next primary.