It’s no surprise that John Schneider and Pete Carroll are going to be running the Seahawks for at least the next four seasons together. Where else are they going to find a better situation than the one they have built in Seattle?

As Schneider told John Clayton on Tuesday, “You look at all the really good organizations: They have great ownership and they have stability. And I think that’s probably what is most attractive here.’’

Schneider and Carroll have put together a team that is poised to contend for Super Bowl titles for at least the next three seasons (see the projected lineup) — and probably well beyond that. Schneider and Carroll have built an organization with similar staying power to Bill Belichick’s crew in New England.

Make no mistake: Carroll, who was replaced by Belichick in Foxboro back in 2000, is planning to continue to win with the same frequency and consistency as Belichick, who has 187 wins in 16 years with the Patriots.

Thanks to his detour for a decade of dominance at USC, Carroll probably won’t ever catch Belichick in NFL win total or even winning percentage (Belichick is at .664, Carroll at .581), but Carroll can still mark his own place in the pantheon of NFL coaching legends.

Carroll, 64, kept his extension short again, adding three years through 2019, but — barring something unforeseen — he surely will stay on past that.

A 15-year stint with the Seahawks would take Carroll to age 73 in 2024. That would make him the oldest coach in NFL history, acing out George Halas and Marv Levy, who both stopped at age 72. (Levy, now 90, will present the late Dick Stanfel at the Hall of Fame on Aug. 6.)

Most great coaches stop by the time they hit their mid-60s. Paul Brown retired at 67 after 25 years with the Browns and Bengals; Joe Gibbs quit at 67 after his second stint with the Redskins; Don Shula retired at 65 after 33 seasons with the Colts and Dolphins; Bill Parcells finally finished for good at 65 after coaching four teams over 19 seasons; Tom Landry was 64 when he was forced out after 29 years in Dallas; Marty Schottenheimer was no longer wanted at 63 after 21 years with four teams.

With the 69-year-old Tom Coughlin fired by the Giants, Carroll has become the oldest coach in the league — he’s seven months older than Belichick. But Carroll is still going strong — a chipper 65 (in September) who acts 45.

As the 45-year-old Schneider said, Carroll is “so positive, so youthful. … He’s just full of life and full of energy.”

The general manager referenced Levy — a nod to the idea that the effervescent Carroll might coach into his 70s.

“He takes great care of himself,” Schneider said. “I think he could go as long as he wants really. … He probably thinks he can live until 120 and coach until 100 (plus).”

That certainly fits Carroll’s mantra: Win Forever. He has repeatedly said he wants “to do it better than it’s ever been done” and he talked as recently as January about how he is driven to reinvent his team’s excellence year after year.

He also knows what he has in Seattle. After losing Super Bowl XLIX to Belichick’s Patriots, he said the Seahawks were “just in the middle of this” run of Super Bowl contention.

Great coaches are defined by their championships, so Carroll needs to make good on what he has built in Seattle.

Thirteen coaches have won at least two Super Bowls — a number that almost guarantees the Hall of Fame for guys who coach at least 15 years. Belichick and Noll lead with four Super Bowl wins each, Belichick’s fourth coming courtesy of Carroll’s coaching gaffe in XLIX and costing Carroll a quick second title that would have put the Hawks in position to create a dynasty this year.

Carroll knows he has his team set up for more of those chances, which is why he is back for four more years — and probably more beyond that.

As he said in January, after the Hawks were bounced from the divisional round by Carolina: “We know that there’s a lot of future and there’s a big upside for us. We have leadership and big-time players and leadership from the quarterback position, which is so hard to find. The connection of what these guys are like on defense really gives us a hope as we go into this offseason that we’re going to do something really special in the future.”