Congressman Joe Kennedy should run for president, argues a Kennedy expert.

The White House is there for the taking in 2020. He believes Kennedy is the most charismatic politician of his generation and can win it.

So argues Larry Tye, a former Boston Globe reporter and a biographer of RFK.

Sure, the old ways would have been to wait for an open Senate seat or governorship, but Trump has changed all the rules.

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To his credit, he won with no political experience on his first try.

In an open letter to Kennedy, Tye made clear how the race could be won.

His grandfather, Robert Kennedy, Tye wrote, waited too long to jump into the presidential race in 1968 when the country was crying out for leadership because of the impact of the Vietnam War. He hummed and hawed and suddenly Senator Eugene McCarthy jumped into New Hampshire’s primary and won an astonishing 42 percent of the primary vote against sitting president Lyndon Johnson.

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Kennedy then reconsidered but looked like a carpetbagger.

“Your brother’s announcement,” columnist Murray Kempton wrote in a telegram to Ted Kennedy, “makes clear that St. Patrick did not drive out all the snakes from Ireland.”

His grandson should not make the same mistake, says Tye.

He cannot dip a dainty toe in then take it back out. There will be a flood of candidates on the Democratic side, most unknown. Kennedy will stand out for all the obvious reasons.

Yes, he will be only forty, but President Macron in France is 40, Taoiseach (Prime Minister) Leo Varadkar in Ireland won at age 38. Youth will beat experience this time around; a combination of both would win the White House from an increasingly deluded 74-year old Trump.

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As for political positioning, Tye argues he just needs to follow the RFK script.

“The RFK of 1968 was a bridge builder — between islands of blacks, browns, and blue-collars; between terrified parents and estranged youths; and between the establishment he’d grown up in and the New Politics he heralded,” Tye wrote.

Boy, do we need a bridge builder.

Tye says mastering the media message will be critical, but he says it is a relatively simple proposition in one sense, which is to be a truth teller.

“Journalists, like everyone, are looking for ... a politician who defies notions of fake news by telling hard truths, and a public figure who remains steadfast despite the pressures of today’s social media and 24/7 news cycle. If you aren’t already thinking about all of this, Joe, it’s not too early — in 2020 you’ll be almost the age Bobby was in 1968.”

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Tye concludes by saying Joe Kennedy has reignited the Kennedy flame. “When you delivered the Democratic response to President Trump’s State of the Union address in January, you reminded many of us of your grandfather — and rekindled the dream of another First Family named Kennedy, much the way Bobby had when he ran half a century ago.”

So the message from one Kennedy admirer is clear, go for it. Joe Kennedy has a lot to think about.

Do you think a Joe Kennedy presidential run could be successful?