Enabled by Democratic senators Joe Manchin and Kyrsten Sinema, a united front of US Senate Republicans dealt American democracy a massive blow last week by blocking the Freedom to Vote: John R Lewis Act. The US Senate: a place where desperately needed federal voting rights legislation goes to die – a spectacle unworthy of what Democratic Representative Jamie Raskin called “the world’s greatest deliberative body”.

Raskin was referring to the Senate’s reputation not necessarily in an affirmative, but in an aspirational way: he wanted to issue a challenge to the senators to live up to this glorious notion. Nevertheless, the mythical idea of the Senate as “the world’s greatest deliberative body” is widely held among the country’s political elite – the kind of American exceptionalism that still very much warps the perspective on US history and politics.

What we really need to grapple with is the fact that the current situation is not just a disgraceful aberration from the Senate’s supposedly noble past and true character. In some fundamental ways, the Senate is working as intended. It has always been one of the most powerful undemocratic distortions in the political system – and not by accident, but because that’s what it was designed to be.

So far, much of the attention has focused on the filibuster as the most blatantly undemocratic tool of obstruction. It is true that the frequency of filibuster use has increased dramatically in recent years. Still, what Republicans did last week was well in line with the longer-term historical norm. The filibuster has consistently been an instrument of white Christian domination: during the 20th century, it was used predominantly to block civil rights legislation and measures such as anti-lynching bills.

Since the filibuster was not part of the Senate’s original design and only came to be by accident in the early 19th century, it is tempting to portray it as the real culprit – a stain on an otherwise admirable institution. Let’s remember, however, that just like the electoral college, the Senate was always intended to be a layer of insulation between those in power and the people – which is why senators were initially appointed by state legislatures. The senate was supposed to help stave off what many of the founders saw as the “threat” of too much democracy. So, what we see today is not just an institution hijacked by a radicalized Republican party (although it is that too) – but an institution badly in need of structural reform that should go well beyond getting rid of the filibuster.

In the current political situation, reforming the Senate, just like protecting voting rights, is considered a “partisan” idea – and it is, but only because democracy itself has become a partisan issue. Of the two major parties, only the Democratic party is a democratic party.

Let’s be specific about how undemocratic an institution this is – something that is best captured in numbers: in the current 50:50 Senate, Democratic senators represent 40 million more voters; by about 2040, 70% of the country will be represented by just 30 senators, while less than one-third of the electorate will get to determine 70 out of 100 members of the Senate.

The issue of disproportionate representation is deeply intertwined with the problem of white Christian patriarchal rule. The Senate privileges conservative white voters who dominate in small, less populous states; it is biased towards white people, with or without the filibuster. Here are two more numbers everyone should know: out of about 2,000 US senators in the country’s history, 11 have been Black. More than 150 years since the civil war, more than half a century since the civil rights legislation of the 1960s – 11 Black senators. And to date, 58 women have served in the Senate. More than a century since Congress passed the 19th amendment, finally granting women the right to vote – 58 female senators. Whenever someone says the Senate is “the world’s greatest deliberative body”, remember that it is deliberately and inherently undemocratic – an anti-democratic distortion that stands in the way of America finally realizing the promise of multiracial, pluralistic democracy.

The legislation Republicans are blocking in the Senate is the minimum needed to resist the state-level authoritarian onslaught on the system. But beyond such immediate measures, a more structural approach to democracy reform is required – and Congress’s upper chamber needs to be at the center of those debates. America can have the Senate in its present form or liberal democracy, but probably not both.

The good news is that serious reform is eminently possible. There certainly is no filibuster requirement in the US constitution, and there are ways to alleviate the Senate’s anti-democratic character – by adding DC and Puerto Rico as states, for instance. The tension between white male elite rule and aspirations of true democracy has always shaped the American project – it is inherent in the nation’s founding documents and its political system. The existing institutional order is in conflict with the promise that all people deserve to participate as equals in a democratic polity – and that situation requires a decision.

“The world’s greatest deliberative body”? If it were true, it would be quite the indictment of the world’s other deliberative chambers. Let’s abandon such vestiges of mythical exceptionalism that make it harder to acknowledge the anti-democratic threats and deficiencies in American politics and culture. The fact that a shrinking minority of white conservatives is consistently being enabled to hold on to power against the will of the majority of voters is destined to cause a massive legitimacy crisis. And unless the system is properly democratized, it is only going to get worse.

• Thomas Zimmer is a historian and DAAD visiting professor at Georgetown University, where he focuses on the history of democracy and its discontents in the United States.