It’s unfortunate, in a nation of 320 million people, that voters must choose the next American president from the disappointing field of candidates now competing in the Democratic and Republican primaries.

We can think of a number of possible candidates — former Republican Gov. Mitch Daniels comes to mind — who might have provided Americans with sounder choices as the nation’s next commander in chief. But that’s not the reality voters in Indiana will face as they go to the polls on Tuesday.

The biggest stakes on Tuesday are on the Republican side, where front-runner Donald Trump could move close to sealing the nomination with another strong win. That would be a disaster in the making.

Trump has demonstrated repeatedly during the months-long campaign that he is wholly unsuited to serve as president. He’s offered simplistic proposals on national security, job creation, immigration, international trade and foreign affairs. He has sounded off with appalling comments about women and others. He’s appealed to voters’ worst instincts by trying to pit racial and ethnic groups against one another. He’s responded when challenged with reasonable questions from political opponents and from journalists with insults and diatribes that fall far outside the bounds of decent political discourse. Those are not the qualities that made America great — or that will make it even greater.

A President Trump would be a danger to the United States and to the world.

Ted Cruz, Trump’s chief opponent for the Republican nomination, also is ill-suited to serve in the Oval Office. His short tenure in the Senate is most noted for his unwillingness to work well with others. Instead of leading and uniting his colleagues in the Senate, Cruz has helped foster even more dysfunction on Capitol Hill with ideological crusades that have done nothing to help strengthen the nation.

During the campaign, as voters have witnessed in Indiana in recent days, Cruz has resorted to bombast and platitudes rather than offer substantive discussion of the nation’s most pressing issues.

The third Republican candidate, Ohio Gov. John Kasich, offers the best choice for voters in the Republican primaries. Kasich built a solid record as a member of Congress and has led well as Ohio’s chief executive.

But Kasich this week cut a disappointing deal with Cruz. Kasich’s campaign pulled out of Indiana in a concession to the Cruz camp and will instead focus its efforts on two western states. The pact is aimed at preventing Trump from winning his party’s nomination. It’s unfortunate that Indiana voters have been given no chance to hear directly from the candidate most qualified to represent the Republican Party in the fall campaign for the White House.

The choice among Democrats essentially comes down to one choice. And that’s not Vermont Sen. Bernie Sanders. He has built his campaign around extravagant promises of a free college education, universal health care and a federal minimum wage of $15. Such proposals are not grounded in economic or fiscal reality.

Sanders, a member of the U.S. House and Senate since 1991, has shown little aptitude for serving as commander in chief or in international relations. He’s simply not well prepared to lead the nation.

Former Secretary of State Hillary Clinton is the stronger of the two and has a deep resume. But she also is hobbled by serious concerns about her judgment and ethics.

Clinton has a history of cutting ethical corners, and two current controversies — her decision to accept large sums of money in speaking fees from Wall Street insiders, and her reckless choice to use a private computer server while handling highly sensitive information as secretary of state — raise critical questions about her judgment.

We are withholding a formal endorsement in either race. Indiana voters can still have a big impact with their ballots Tuesday in halting Trump’s march. The best we can hope is that Hoosiers do just that — and say no to a candidate who is not merely flawed but is clearly unfit for the office he seeks.