Watch out NBA fans, because I’ve got some scary, scary news for you: LeBron James has a jump shot.

The Cavaliers’ phenom achieved superstardom during the past two seasons despite a mediocre delivery from outside. It was a strongshortcoming:Heonlymade 31.9% of his 3-pointers and 34.8% of his long 2-pointers last year, according to NBA.com, well below the norm for a perimeter player. But even with that shortcoming, he nearly won the MVP award two years ago, and carried his team to the Eastern Conference title last season.

During this summer’s FIBA Tournament of the Americas, he unleashed his new weapon. James looked much more balanced and comfortable on his jumper, after hinting that he’s been working on the shot since Cleveland lost in last season’s NBA Finals.

The work paid off, because he was vastly more accurate. James made 23 of 37 3-pointers in the tournament, a ridiculous 62.2% from downtown. Even granting that the international 3-point line is shorter, and that the competition this past week was not exactly daunting, and that 37 shots is a small sample — this was an impressive showing.

Furthermore, look at how hard it made life for teams trying to defend James. Having to guard him for the 3 meant it was impossible to cut off his drives — he shot an absurd, incomprehensible 50-for-59 on 2-pointers. His shooting percentage overall was a video game-like 76%, and he led the U.S. team with 47 assists in 10 games. Despite the embarrassing selection of Argentina’s Luis Scola as the tournament MVP — attention, worst-award-vote-in-history debaters, we have a new candidate! — James was easily the best player in the tournament, as America won the gold.

While the talk after the competition has focused on what the tournament means for the U. S. team’s chances in Beijing next year, I’m focusing on a more shortterm target: what it means for the other Eastern teams next year.

The sentiment going into the season has been that the Cavs were an unimpressive conference champion, and the possibilities are wide open in the East. But the other clubs in the conference need to consider that things will be very different this time around.

James didn’t exactly come out like gangbusters in the regular season last year. He pretty much admitted to mailing it in the first halfoftheseason, andhisnumbers in every major category dipped from his epic 2005–06 campaign.

But what if James plays like, well, Superman? The Cavs already have a fantastic front court and defense, something the “it’s just LeBron and a bunch of garbage” crowddoesn’tseemtounderstand. While their back court isn’t any good, it’s not like it can get any worse than it was a year ago.

If they were able to win 50 games with James clanging jumpers, how many might they win if James plays at an MVP level? At a runaway MVP level? At — dare we say it — a Jordanesque level? It’s a question worth asking, because if James shoots like this, there isn’t anybody in the league that can guard him. I’m not sure if there are any two players that can. He’s a6-foot-8-inch,240-poundfreight train who handles the ball like a point guard, and the only thing making him remotely defensible is that opponents could play five feet off him and only hope that he’d miss the jumper. But what if he’s settled in shooting that jumper, instead of hesitating before fading away and drifting to his left like he did last year? How, pray tell, could one even guard him then?

All of our talk about Boston or Chicago or even New Jersey becoming a contender suddenly seems almost completely irrelevant. If James shoots 40% on 3-pointers, there aren’t going to be any other contenders. The East will be the Cleveland Invitational, and everyone else will be playing for second.

That — and not the implications for Beijing — is the main conclusion from the American side’s destruction of the field in Las Vegas these past two weeks. But since 11 other guys were out there with King James, let’s also talk about America’s impressive performance — one that entrenches them as the gold medal favorite in Beijing next summer.

This is the first American side I remember that looked comfortable playing international basketball. Carmelo Anthony is an incredible scorer under these rules because the closer 3-point line is just inside his range, and the team seemed to fit together seamlessly around him and James. Kobe Bryant relished his role as defensive stopper, Michael Redd proved a dangerous sniper off the bench, and Dwight Howard controlled the paint.

Coach Mike Krzyzewski also gave an early hint as to who might make the team next year. He stuck with a starting five of Jason Kidd, Bryant, Anthony, James, and Howard; and he used a bench unit of Michael Redd, Chauncey Billups, Tayshaun Prince, and Amare Stoudemire, until the scoring got out of hand. The other three — Tyson Chandler, Mike Miller, and Deron Williams — seem likely to be on the outs next summer.

Of course, plenty can change between now and then — the roster for Beijing isn’t due until June 28. Perhaps James and Anthony will be too worn down by the thought of three straight summers of international ball and pull out. Maybe somebody will blow out a knee or pull a hammy. Also, who knows what players might break out and make a bid for a roster spot.

It’s too early to say if U.S. will trash the field in Beijing the way it did in Las Vegas. But it’s not too early to warn the East about James. Watch those jumpers in preseason and the opening weeks: If they’re falling, the East won’t be as wide open as people suspect.

jhollinger@nysun.com