Hillary Clinton delivered a surprisingly populist victory speech on Tuesday night after winning the majority of the Democratic Party’s presidential nominating contests earlier in the day.

“Let there be no doubt,” the former secretary of state warned businesses, “if you cheat your employees, exploit consumers, pollute our environment or rip off the taxpayers, we’re going to hold you accountable.”

Only if companies do the “right thing,” she said, “if you invest in your workers and in America’s future,” will they have her support as president.

The anti-business rhetoric was unexpected from a candidate who is often seen, at least inside her own party, as too close to business. Her opponent, Bernie Sanders, a self-declared socialist whose sole goal in politics is to fight the money interests, is clearly forcing her to tack left.

Maybe Clinton thinks she can afford to, given that the Republican Party is in such a disarray this year that it cannot possibly defeat her in November.

If that’s the case, she should think twice.

Ups and downs

The logic may seem compelling and Clinton wouldn’t be the first politician to assume that the extremism of her opponents gives her ideological breathing space.

Some Conservatives in the United Kingdom, for example, are similarly calling on Prime Minister David Cameron and his deputy, George Osborne, to pursue a less compromising right-wing policy now that Labour has wandered off into the electoral wilderness.

But at some point Britain’s Labour Party will come to its senses and find its way back to the middle. Probably with a lot of hoopla and when the other party has grown stale in power. It’s what it did under Tony Blair.

Clinton ought to remember. It was her husband, Bill, after all who pulled off a similar stunt in the United States around the same time. He made the Democrats electable again by moving them to the center.

At some point, Republicans will recognize they need to do something similar. Not this year. Perhaps not even in four years. But a political party is only satisfied staying out of power for so long.

When Republicans finally remember that elections are won in the center and reinvent themselves accordingly, it will be much easier for them to win again if the Democrats have indulged their left-wing passions.

Clinton should look beyond this election and the next. For the sake of the Democratic Party’s long-term prospects, she must avoid the temptation of veering too far to the left.