(CNN) Nikki Haley's resignation, to be tendered at the end of the year, caught official Washington by surprise -- because she's not leaving for another public office, even though she would seem to be at the height of her political power.

Surprising, perhaps, and certainly intriguing for the prevaricators to wonder what exactly she's up to, but her move is not without precedent. In fact, Haley is the second very powerful rising star in the GOP to announce that she's basically taking some time off from public service, the other being Paul Ryan.

They're both young Republican politicians -- she's 46 and he's 48 -- who found great success early on and are now leaving politics. At least for now.

Could this be a coincidence? Sure! Or it could mean that some of the top Republican talent not named Trump thinks that winter is coming, to put a Game of Thrones spin on it

They'd rather not be directly in the conversation for the next few years and whether they'll admit it or not, that says something about where they think the conversation is going.

Republicans right now are at the height of official power. Ryan is leaving as speaker of the House before the likely possibility that Republicans are out of the majority next year. Haley announced she is leaving Trump's Cabinet ahead of a likely difficult election night when, if polls are correct, women could turn against the GOP in a way unseen in recent elections

Plenty of Republicans -- a remarkable number, really -- were already retiring this year rather than face tough re-election campaigns. Senators like Bob Corker of Tennessee and Jeff Flake of Arizona, both critics of President Donald Trump, bowed out of bids for re-election. But that feels different than Ryan, who almost certainly could have stayed in charge of House Republicans, even if not in the majority, and Haley, who could certainly have kept her seat of power in Trump's Cabinet.

People who get to the level of Ryan and Haley do not, as a rule, hang up their spurs for years on end when there's a next obvious step for them to take.

This is a very different spin on politics than Teddy Roosevelt's insistence that the highest respect should be reserved for " the man in the arena ." Or woman, in this case. They're both on their way out of the arena. (Note: Roosevelt left politics after being president and when he tried to come back it didn't work out quite so well for him .)

What their decisions mean is that the next obvious step is closed. Why? Because the party has rallied around Trump. And neither Haley, despite her service in his Cabinet, nor Ryan, despite his work with Trump on tax reform, could even remotely be considered Trump Republicans. She endorsed both Marco Rubio and Ted Cruz before she got to voting for Trump in 2016 and Ryan was slow to endorse the party's nominee despite his status as speaker of the House.

We should note here that there are surely other considerations at play for both Haley and Ryan. Neither specifically listed two of the most obvious motivators reasons that make their announcements make sense -- they could both use the opportunity to make some money. Haley has one kid in college and one in high school.

Ryan, whose father died when he was young, sincerely argued he wanted to spend time with his children before they grew up and moved out.

Timing is everything in politics, and the time is not now for either of them.

"This really was two things," Ryan told reporters back in April when he announced he'd be leaving Congress. "I have accomplished much of what I came here to do, and my kids aren't getting any younger. And if I stay, they're only going to know me as a weekend dad, and that's just something I consciously can't do. And that's really it right there."

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Haley did not give a very specific reason Monday, but she, too made sure to say she'd done what she set out to do.

"I don't have anything set on where I'm going to go," she said. "I think that the main thing was -- I was governor for six years, and we dealt with the hurricane, a thousand-year flood, a church shooting, a school shooting. There was a lot. And then, to come in and do two years of Russia and Iran and North Korea -- it's been eight years of intense time, and I'm a believer in term limits."

It's usually after a failed presidential run that politicians of Haley's and Ryan's caliber leave politics, often to return after squirreling away some private sector money. That's what Ohio Gov. John Kasich did. He's kept himself very much in the mix and remains one of the few Republicans unafraid to criticize Trump even as he sidles further from the core of Trump's GOP.

There is some political danger in the years-long money-making sabbatical. Hillary Clinton lost to Barack Obama in 2008, served as his top diplomat, had some of the highest approval ratings in the country and then spent two years making gobs of money giving speeches to Wall Street firms. That money-making break hurt her in the Democratic primary, when it was a key talking point of Vermont Sen. Bernie Sanders.

If Ryan and Haley cash in, they won't any longer be able to say they've been toiling in public service.

Most presidents come to office straight from another government job. Trump, the real estate tycoon and reality show star, is a very notable exception.

But George W. Bush, Barack Obama, Bill Clinton and George H.W. Bush all had a government job just before going to the White House. Ronald Reagan went from being governor of California in 1975 straight to the campaign trail, but lost the 1976 GOP primary. He stayed very active politically and cooled his heels for 1980.

One of the few politicians to successfully land a return from the political wilderness was Richard Nixon, although his came after a long career in the House, Senate and eight years as vice president. He lost a race for California governor and sat out the 1964 presidential election after losing a squeaker in 1960.

A big difference is that Nixon's losses exiled him to the political wilderness. Ryan and Haley are going willingly into it.