Michigan Rep. Justin Amash was never exceptionally deferential to his party. For four years, his Twitter cover image has been the 2015 winner of an annual high school art competition in his district. It's an unsparing indictment of partisan bickering: an illustration of two baboons absurd in 18th century frippery, mirror images of each other except their red and blue team colors and locked in a mutual scream.

So perhaps Amash's July 4th declaration of independence from the GOP should come as no surprise. "Preserving liberty means telling the Republican Party and the Democratic Party that we'll no longer let them play their partisan game at our expense," he wrote in a Washington Post op-ed announcing and explaining his decision. "No matter your circumstance, I'm asking you to join me in rejecting the partisan loyalties and rhetoric that divide and dehumanize us."

Any high-profile departure from either major party is intriguing, but Amash's move holds a special interest for me: He is far and away the House member I respect and agree with most on principle and strategy alike. Where other comparatively libertarian Republicans have played nice with President Trump in an effort to influence him for the better, Amash has been bold and consistent in public critique of his now-former party's leader. That may be neither "safe nor politic nor popular" — see The Week's Jim Antle on this tactical divide over at the Washington Examiner — "but he must do it because conscience tells him it is right."

Leaving the GOP may be the right move, too. It's at least understandable. I share all of Amash's views about partisanship as elucidated in his Post piece, and, in his position, I might bolt the party, too. But that understanding doesn't stop me worrying about what this means for Amash's political future. He may be the most principled man in Washington — he's certainly the most visibly libertarian — so I'd like to keep him in Washington.

Where re-election to the House for a sixth term is concerned, I'm not terribly anxious. Amash is popular in his district, where he has made no secret of what he believes. "I've been very clear about it in the years I've run for office that I am a libertarian philosophically, and people have voted for me," he said in an interview with Vox published Wednesday. "They voted for me in the Republican primary, they voted for me in the general election, and I won by larger margins in both cases than most other candidates running."

Going independent also allows Amash to sidestep the primary challenge launched in response to his break with the Republican Party over impeaching Trump. I don't make election forecasts as a rule, but if I had to guess, I'd say independence improves Amash's House race fortunes for 2020: A Trumpist Republican could conceivably win in the GOP primary but is unlikely to triumph in the general election in Grand Rapids.

The more pressing concern, perhaps, is the prospect of a presidential run on the Libertarian Party ticket. The possibility has been raised since Amash's impeachment comments went viral this spring, and he has declined to rule it out. Amash is young, charismatic, and principled, note proponents of an LP campaign. He is free of the bizarre baggage (e.g. John McAfee's whole murder thing in Belize) and missteps ("What is Aleppo?") of LP contenders past. He would never strip on C-SPAN or discuss the merits of selling heroin to kids. Perhaps he could go where no libertarian has gone before: the general election debates. Perhaps he could make a smart and winsome case for libertarianism before the largest audience on offer.

I would love to see Amash debating — and yet I'm convinced an LP run is a bad idea, especially for 2020. In any election, the system works against third-party candidates. As I explained here at The Week in 2016, a candidate must demonstrate 15 percent national support to be invited to the debate state. But it is incredibly difficult to gain that support before a debate appearance — and the debates are organized by Democratic and Republican Party leadership, who have no interest in facilitating third-party inclusion.

The debates also aren't the only problem: Electoral failure is a foregone conclusion because of how our voting system is structured. No third-party candidate stands a chance unless we make major institutional changes in our elections. Voters realize this, even if they can't articulate the exact impediment to third-party victory. This is why many who might be inclined, as a matter of principle, to vote LP or Green Party or whatever instead cast a major-party ballot or skip voting entirely. As a means of registering unmistakable protest of the major-party options, a third-party presidential vote isn't wasted, but as a means of actually electing someone to office, we all know it's usually useless.

This is particularly so for the presidential race in 2020, where Trump's involvement promises an extra degree of partisanship and polarization. Voters who might in other years be willing to consider a cogent third-party contender will, in this cycle, give short shrift to a potential spoiler. If Amash were to run for president, he would be advised to do it as a Republican (much as Sen. Bernie Sanders is an independent in the Senate but seeks the Democratic nod) — or at least to wait until we have a Trump-free field in 2024.

Finally, I caution against a 2020 LP campaign because of the unfortunate effects a failed presidential run can have for a political career. While some politicians can retain their stature after losing the White House, many more cannot, especially if a gaffe (like Aleppo, the Dean scream, or the Dukakis tank photo) comes to define their rise to national prominence. More than two losing campaigns is distinctly bad, which makes crucial choosing the right year to run. If Amash has only one or two shots to plausibly campaign for president, blowing one on 2020 is unlikely to serve him well.

The aim of Amash's rare and risky stand against partisanship was not personal political gain. Hopefully its effect will not be personal political loss, because his independent voice is precisely what Washington needs.