WASHINGTON — The starting pitching-rich Mets tried to use the Nationals as a template of success, a way to climb out of the hole they put themselves in this season and it never worked out.

For the Nats, though, this has been a dream comeback season after their 19-31 start. They are one win away from going to the World Series.

Finally, after years of playoff failure, true Natitude.

The Nationals can become the first team from D.C. to go to the World Series since the 1933 Senators lost to the New York Giants in five games.

Amazing how it all turned around. They came back from a late deficit to win the wild-card game against Milwaukee, they battled back to beat the Dodgers on an extra-inning grand slam after being down late in Game 5.

Now, they are putting on a pitching clinic to completely shut down the Cardinals.

Stephen Strasburg was magnificent Monday night as the Nats crushed the Cardinals, 8-1 at Nationals Park to take a 3-0 lead in the NLCS. The right-hander struck out the last two batters of the seventh, and when he K’d Dexter Fowler with his 117th pitch he triumphantly ran off the field.

Strasburg struck out 12, did not walk a batter and the one run allowed was unearned. The Nats starters in the NLCS — Anibal Sanchez, Max Scherzer and Strasburg — have pitched 21 ²/₃ innings and have not surrendered an earned run. They’ve walked three batters.

You can keep your “bullpenning.’’ Natitude begins with starting pitching.

“These guys all feed off each other,’’ Nationals elder statesman Ryan Zimmerman said. “They’re built for this. And that’s what you build a team around. Teams kind of shy away from that now. These guys do things that are not asked any more of pitchers in this generation.’’

Indeed. Strasburg owns a 1.10 career postseason ERA. The only ones better, minimum six starts, are Sandy Koufax (0.95) and Christy Mathewson (1.06).

Said Strasburg, “Back in May we kind of knew the [starting pitching] would kind of have to carry us. It’s just been such an amazing year, it has really been great from where we had to come from. We got such a great group of guys, it’s just fun being around the guys and competing together. We just want to stay together and keep playing.’’

Teammates also have their fun with the cool and calm Strasburg and make sure to hug him in the dugout.

“When he comes back into the dugout guys like to love on him a little bit,’’ Adam Eaton said.

“I’m not much of a hugger,’’ Strasburg said with a smile, “but I kind of have to take it.’’

It was a party for the 43,675 at Nats Park from the third inning on as the Nationals ran out to a 4-0 lead against Cardinals ace Jack Flaherty.

All four runs came on two-out hits as Adam Eaton singled home a run, Anthony Rendon doubled home another and Howie Kendrick, who hit the grand slam to beat the Dodgers in the NLDS, lined a two-run double to right-center for two more runs, the first of three doubles he hit Monday night.

Opponents hit .192 against Flaherty during the season, but not these Nats.

The Nationals became the ninth team in MLB history to come back from 12 games under .500 (19-31) to make the postseason. They are trying to join the 2005 Astros, 1973 Mets, 1914 Boston Braves as the NL teams to make the World Series after being 12 games under.

There is a certain amount of toughness a team has to show to come back from such a deficit. GM Mike Rizzo was more determined than ever to have tough, team-first players after the Nationals have crumbled in so many past postseasons.

The irony is the Nationals allowed superstar Bryce Harper to walk away to the rival Phillies as a free agent.

“You look of the résumés of our starters and that’s the reason when we were faltering we did not throw in the towel,’’ Eaton said.

Great starting pitching takes the pressure off an offense. The Nationals are 15-2 since Sept. 23 and the starting pitching, Rizzo’s rock, has done its job. Washington’s starting rotation, emotionally and physically led by Scherzer, is 5-1 through nine postseason games.

The Nats, with those powerful starters, have found the true meaning of Natitude, finally, one glorious win away from the World Series.