A small but significant group of Americans is considering casting their vote this fall for a third- party “protest” candidate. Some are thinking they may not vote at all. They say they don’t like any candidate enough to vote so they will “sit this election out.”

I realize many of the Americans considering a third-party vote — or sitting out the election — have sincere, deeply-held feelings that are driving their actions. Some are just disgusted by what they think is a vitriolic tone of the campaign.

Unfortunately the media encourages that kind of cynicism and disgust by presenting the attacks mounted by each side in the campaign as equally credible.

But while it is easy to understand the reasons that some people might be inclined to choose a “protest” vote — or decide to sit on their hands — the fact is that either of these actions will have one and only one result: putting Donald Trump into the White House.

And “trust me,” the election of Donald Trump as President of the United States will have long-term consequences that will make it ever so clear why every voter has to overcome his or her cynicism, or personal likes and dislikes, and go vote — for Hillary Clinton.

History makes the results of third party “protest” votes in modern American elections crystal clear.

In 2000, thousands of idealistic young Americans chose to vote for Ralph Nader rather than cast their vote for Vice President Al Gore. There were 50,000 Nader votes in Florida. Gore lost the presidency by 537 Florida votes.

Had Gore won, there would have been no Iraq War in 2003 — and likely no ISIS today. There would have been no Bush tax cuts for the rich. There would not have been the massive Bush-era deregulation of Wall Street that led to the Great Recession.

And for those who care deeply about climate change, remember that it was private citizen Al Gore who, after losing the election, sounded the climate change alarm with his amazing film “An Inconvenient Truth.” Had Gore been President, the United States of America would likely have initiated the battle to curb global carbon emissions over a decade and a half ago.

And you can bet that if they knew what would happen in a Bush presidency, many of those 50,000 Nader voters would have begged to reverse history and let them vote for Al Gore for President instead of cast the “protest vote” that cost us all so much.

Of course it’s not just the 2000 election where third-party protest votes have been decisive. The election of Ronald Reagan in 1980 — and the whole right wing “Reagan Revolution” — would likely never have happened, were it not for the third party candidacy of John Anderson.

Remember that none of the 2016 third-party candidates has any credible chance whatsoever of becoming President of the United States.

Someone who casts his or her vote for one of these third-party candidates must be betting that the results of their own “protest” are more important that the consequences that a Donald Trump Presidency would have for the country — and for their lives.

But I would wager that a significant number of those 2000 Nader Voters personally suffered from the consequences of Bush’s two terms in office. Odds are good that many of their families lost loved ones in Iraq, or that their home values collapsed in the Great Recession, or that they lost their jobs or their pensions, or saw their college loans explode. Many suffered from rising health care costs that Bush failed to address through any form of health care reform.

I’m betting that many of those voters would agree today that whatever momentary sense of power they felt by sticking it to the system and protesting their presidential options in 2000 is now far outweighed by the regret they feel at the consequence of what they did.

If you’re considering casting your vote for a third party candidate, or simply abstaining from voting entirely, please think seriously about how you’ll feel about that vote next year, or ten years from now — if, like the Nader voters of 2000, your votes determine who will be president.

It’s one thing to cast a “protest vote” or decide to stay home, if you think the election is already decided. A month ago many people thought Hillary Clinton would run away with the election, so why not vote for a third party candidate? Not so today.

That’s exactly what happened in Britain during the Brexit vote earlier this summer. Many voters — especially younger voters — who opposed Britain leaving the European Union — thought they didn’t need to go to the trouble to vote because Brexit could not possibly pass. The day after the election, they were shocked to learn they were wrong — and then it was too late.

Polls showed that young people overwhelming opposed Brexit. But many of them didn’t take the time to vote. Now they wish they did.

Today, most millennial voters oppose the bigotry of Donald Trump. They also understand that a man with Trump’s temperament has no business with the country’s nuclear launch codes.

They want lives of commitment for themselves. They honor the sacrifice of leaders like Martin Luther King, Jr., and Congressman John Lewis who were willing to lay their lives on the line for the welfare of others. And they understand that Donald Trump is the antithesis of a leader who has devoted his life to others and to the common good. They know that Donald Trump is a man who has done nothing in life but look out for himself — no matter who he hurt, no matter whose lives he ruined.

But if Donald Trump is actually elected President, that division, that hatred, that bigotry, that selfishness and the impetuous childish insults will define America. They will be our future.

In a close race like this one, no one can afford to make a “protest vote” that may end in that result. No one can afford to say: “my vote doesn’t matter.” No one can afford to allow their own disappointment with the result of the primary — or their wish that someone who is more to their taste were the candidate — to contribute to such an historic disaster for America and the entire world.

In many states, early voting — or mail balloting — starts in a matter of weeks.

If you were thinking about casting your vote for a third party — or staying home from the polls — please think again. You, your children and maybe even your grandchildren, will be glad you did.

Join us in stopping Trump. And in the process, help make history by electing the first woman president of the United States. Cast your vote for Hillary Clinton.