The youth vote could decide the 2020 election, and yet it is being suppressed.

The hurdles for young voters are many. Residency requirements, strict voter ID laws and inaccessible polling places affect voters of all ages, but they particularly abridge youth voting rights. College students living and studying away from their family homes have to establish residency in their new locations to register to vote. Many states have prohibited the use of student ID cards for voter identification, requiring in-state drivers’ licenses. These and other policies burden the rights of young voters.

The havoc wrought by covid-19 on colleges and universities is only going to compound these difficulties.

This situation led to a challenge to a Texas policy that recently came before the Supreme Court. Under Texas law, only registered voters who meet certain criteria — including being 65 or older — are qualified to request a mail-in ballot. But the 26th Amendment states that the right to vote for citizens 18 and older cannot be denied or abridged because of age. “Whatever right to vote a state creates — whether it involves polling hours, early voting, or vote-by-mail — must be extended to all voters without regard to their race, their sex, their payment of a tax … or their age,” argued Texas Democrats in their lawsuit challenging the state’s law.

A trial judge issued an injunction requiring that the state permit all voters, regardless of age, to use mail-in ballots. The U.S. Court of Appeals for the 5th Circuit stayed this injunction pending an appeal, and the Supreme Court declined to step in, despite Justice Sonia Sotomayor noting that it “raises weighty but seemingly novel questions regarding the Twenty-Sixth Amendment.”

Sotomayor is right. For most of its almost 50-year history, the 26th Amendment has been understood as giving 18- to 21-year-olds the right to vote. But like the 15th and 19th amendments, the 26th does more than merely extend the formal right to vote. It also prevents the state from imposing discriminatory burdens on voting rights. Sotomayor’s note serves as a timely reminder of the historical significance, contemporary relevance and untapped potential of this amendment.

Passed and ratified in 1971, the 26th Amendment culminated a multifaceted campaign for youth voting rights in the United States. Over a 30-year period from World War II to the early 1970s, Americans old and young, Democrat and Republican, built momentum and then a movement for the 26th Amendment.

The push for youth voting began in the 1940s. Georgia in 1943, Guam in 1954 and Kentucky in 1955 lowered their voting ages. In 1959, the new states of Alaska and Hawaii instituted voting ages of 19 and 20. These achievements laid the foundation for the 26th Amendment.

Proponents of youth voting rights advanced multiple arguments. Young Americans had the maturity and education to vote. Their enfranchisement would strengthen democracy in the United States by allowing more citizens to participate in politics and elections. And most influentially: During World War II, the draft age for military service dropped to 18, yet voting remained a right gained only at 21. The rallying cry “old enough to fight, old enough to vote” grew louder with the Korean War and louder still with the more controversial Vietnam War.

But the battle was fierce. Opponents countered all of these arguments. Multiple state referendums went down in defeat in the 1950s and 1960s; South Dakota voters rejected the 18-year-old vote twice. In Congress, opponents insisted that the power to set voter qualifications belonged to the states and refused to act on a constitutional amendment — until 1971.

It was only in the climate of the 1960s that an amendment became possible. The timing of this expansion of American democracy shows how young people and their allies successfully worked within the political system to change the system. Building on the decade’s many social movements — civil rights, student and antiwar movements — young Americans built an alliance, the Youth Franchise Coalition, established in 1969, and supporters came from a broad, bipartisan group of Americans to try to make a final push for youth voting rights.

National, multi-issue associations, such as the National Education Association, the NAACP, the League of Women Voters and the AFL-CIO, committed people and resources, while new groups dedicated solely to lowering the voting age launched. Proponents of the 18-year-old vote came together on this one common goal without having to agree on everything, or even anything, else, and achieved a constitutional amendment that benefited every constituency in the nation.

Passage of the amendment capped a decade of constitutional revisions and a dramatic expansion of suffrage with the 1964 Civil Rights Act and the 1965 Voting Rights Act.

But the record vote for approval in the Senate (94 to 0) and the House of Representatives (401 to 19) and the record speed with which the states ratified the amendment — in fewer than 100 days — masked the long, arduous campaign behind the amendment, which is relevant today amid new youth activism.

The 26th Amendment also has great contemporary relevance. Since 1972, the first presidential election with a national voting age of 18, voter turnout among youth has been significantly lower than turnout among older voters. That year, as well as 1992 and 2008, represented the highest participation rates for young voters — until the 2018 midterm campaign.

The recent youth vote — unprecedented for midterm elections — can be seen as an unequivocal repudiation of a reactionary president. It also must be understood as a result of rising youth activism around a range of issues that disproportionately affect young people. Climate change, gun violence and police brutality have spurred new movements and actions, including School Strike 4 Climate, March for Our Lives and Black Lives Matter. Calls for further lowering the voting age to 16 have multiplied in this context.

But for young voters to capture the attention of politicians and see their policy proposals enacted, the youth turnout has to match the turnout for older age groups with different politics.

This is difficult, given voter suppression laws. But legal challenges continue in Missouri and Alaska, and arguments based on the 26th Amendment have the potential to counteract these laws for voters of all ages. After all, the wording of the amendment prohibits age discrimination in voting rights broadly and could benefit a range of age groups affected by voter suppression, as with 18- to 64-year-old Texans in the recent case.

Properly interpreted — as Sotomayor suggested — the 26th Amendment establishes a broad constitutional prohibition against age discrimination in voting rights and grants Congress extensive powers to ensure state compliance with that prohibition. These powers allow Congress to take bold action to protect the rights of students, senior citizens and any other group whose members suffer franchise discrimination on account of their age. For these reasons, the 26th Amendment warrants our greater attention, appreciation and application.