No team in the history of American pro sports has ever been in as much trouble — a legal, ethical and disciplinary nightmare — as the St. Louis Cardinals are now if an FBI and Department of Justice investigation ultimately proves that members of their front office hacked the computer network of the Houston Astros to steal . . . everything.

Government investigators are probing the Cardinals to see whether their employees hacked into the Astros’ main proprietary baseball brain — called Ground Control — which was developed by former St. Louis front office star, and now Houston general manager, Jeff Luhnow.

If proven true, this could in theory lead to jail sentences for the guilty as well as possible lifetime bans from baseball on “integrity of the game” grounds. Neither MLB, nor any other major American sport, has a precedent for punishments in such a case because no team has ever attempted such wholesale club-against-club spying, ostensibly in search of a mountain of team secrets.

But, depending on many variables — especially who knew and who (if anyone) authorized such theft — MLB might need to deliver the harshest penalties against any team in the game’s history. This investigation has the potential to make the NFL’s DeflateGate look like a probe into jaywalking.

For more than a century, baseball has been known for its relatively minor forms of rule-bending or cheating-with-a-wink, such as spitballs and corked bats. In perhaps the most egregious example of true team-wide cheating, the 1951 New York Giants had a sign-stealer with binoculars positioned in their center field scoreboard in the Polo Grounds to relay the pitch to their hitter at the plate.

Even that was chicken feed compared to what the Cardinals may face.

What would be inside Ground Control that could be of value to a competitor? Probably every shred of information the Houston franchise possesses on virtually anything of vital importance to its entire operation. You name it: proprietary evaluations of current MLB players as well as reports on amateur players who might be drafted or signed in the future; Moneyball-type analysis of how every aspect of the game should be played; how statistics should be evaluated as well as the Astros’ internal discussions of potential trades or free agent signings.

If true, it would be hard to imagine how you could cheat in baseball on a bigger, more damaging or more potentially criminal scale. In fact, the scale of the possible espionage — the combination of no-conscience audacity, plus the stupidity of risking going to jail if caught and convicted — makes it difficult to believe that any team owner, president or general manager would get involved in such a thing. That the Cardinals, one of baseball’s most respected and successful franchises, are the team being scrutinized makes the shock even greater.

Even if lower-level front office personnel are nailed, the penalties MLB would almost have to impose could be the most severe in baseball history. How could any sport establish a precedent for leniency just because a club managed to maintain “plausible deniability” up its chain of command? “It was a few bad apples” can only mitigate so much.

In coming days and weeks, this story will produce many tangents that may distract us from the central point. For example, if the investigation does implicate Cardinals employees, what were the motives of the possible spies?

Was there resentment or jealousy within the Cardinals front office toward Luhnow, a former colleague who was instrumental in trades, signings and key decisions that helped the Cardinals win two World Series during his time in St. Louis? Was mere malice and mischief-making as much in play as serious espionage?

How much damage could such database larceny actually do to the Astros, because Luhnow has commented publicly on how much he believes in “transparency” so Astros fans can understand the sometimes unorthodox reasoning and data behind the team’s personnel decisions and playing strategies?

Were there internal walls within Ground Control that would limit how much information a hacker might get? For example, an Astros scout might have a password that allowed him to see only a fraction of the total data mine.

Were the Astros lax or even inept in some cases in using simple or easily hacked passwords to gain access?

While such sidebars may be interesting, they avoid the main point. In recent times, baseball has undergone a top-down revolution in almost every corner of the sport — driven by front office brainpower. In Houston’s case, its attempts at gaining cutting-edge advantage were probably in Ground Control.

On many teams, mathematical analysis of statistics is now routinely done by MIT PhDs or former Wall Street quantitative analysts. Some teams use psychological profiles to aid in building a cohesive, compatible team. Defensive shifts and alignments, derived from high-tech analysis of the flight of every batted ball, are guarded like gold. Merely measuring the speed of the ball as it leaves the bat is yesterday’s data. Now, what is the correct angle of pursuit to chase a flyball in the gap? Which fielders have that knack and which ones look good chasing that fly but don’t get it?

In this century, baseball has been the cutting-edge brain game with other sports, especially the NBA and NHL, trying to catch up. There are few bigger questions among those who run MLB teams than “What can we study next? Where can we find a ‘market inefficiency’ and thus a tiny edge?” Now, it’s food.

For a century, the only thing “proprietary” in baseball was the fact that you owned the land under the ballpark. Now many teams, such as the Red Sox, who have won three World Series since 2004, run on ideas as much as athletes.

That’s what is so disturbing about the investigation of the Cardinals. To the baseball mind of 1955 or 1985, stealing “data” or poaching “ideas” would seem peculiar and not worth the risk of being caught.

In 2015, hacking into Ground Control is exactly what a smart, ambitious team might do if it were unscrupulous and understood that the right “data and ideas” are the most valuable things you could possibly steal from a business rival.

Are the Cardinals innocent and falsely suspected? Absolutely possible.

Did a couple of low-level rockheads in St. Louis figure out the passwords to some of their old buddy/enemy’s computer archives and sneak a peek? Maybe.

Or did front office employees of one of the best-run, smartest and most cutting-edge franchises understand that hacking Ground Control was a huge risk that might have huge rewards in stolen secrets?

Whatever the truth turns out to be in this case, pro sports have taken a new turn. We’re no longer worried about stolen signs from center field or videotape of a football practice or, for heaven’s sake, the air pressure in a football.

Now, and forever forward, every team in every sport will have to understand that the ultimate cheating, the worst possible theft, worthy of the most severe legal and league punishments, is to steal another team’s brains.