The Dictionary of Modern Strategy and Tactics defines deterrence as: “The prevention or inhibition of action brought about by fear of the consequences. Deterrence is a state of mind brought about by the existence of a credible threat of unacceptable counteraction. It assumes and requires rational decision-makers.”

For a nonterrifying example of deterrence in our steadily darkening world, look no further than the recently expired NBA trade deadline. The Warriors and the Cavaliers have been the league’s dominant superpowers for the past two seasons. LeBron’s fiefdom has shown signs of vulnerability of late (more on this shortly), but the point stands. James is still the best basketball player on the planet. As long as the King remains upright on the chessboard, the Cavs are in the game. Meanwhile, the Warriors have four of the best 20 players in the NBA and finished the first half of the season by revving their hyperspace engines to increasingly otherworldly levels. The Space Dubs have a window of a couple of years before a cap crisis could trigger the breakup of their nuclear core.

If, per the definition of deterrence, you’re a rational decision-maker running an NBA team, you look at that two-year span and think, “Do I feel lucky?”

Clearly, from the relative paucity of deadline deals, many teams are not in a gambling mood.

Prime example: Danny Ainge and the Celtics. The state of perpetual dryness in which Ainge keeps his powder has become something of a running joke among #BestSport aficionados. In the summer of 2013, Ainge, his hand held in the shape of a gun pushing through the waist pocket of his windbreaker, mugged Billy King and the Nets in broad daylight, right in the middle of Atlantic Avenue, making off with basically all their future draft picks. He’s been eagerly collecting dealable pieces like a front-office pizza rat ever since.

As a person who just likes watching fireworks go off, Ainge’s position is somewhat maddening to me. The Celtics have a fistful of assets, a logjam in the backcourt consisting of numerous dudes who will need to get paid soon, and clear holes waiting to be filled. The C’s need another star-level player to take the load off of micro-size terminator Isaiah Thomas. A rim protector would be nice, and it would be even better if he could rebound too.

Despite being linked to moves for Chicago’s Jimmy Butler and Indiana’s Paul George — two really good basketball players theoretically capable of pushing the Celtics past the wounded Cavaliers — we got nada. Nothing. Any deal for Butler or George would’ve required the Nets’ 2017 pick. Ainge’s lack of movement was annoying, a direct contradiction of the universal ethos that shooters must shoot. And, yet … it makes sense from the perspective of deterrence theory.

Do the Celtics plus Butler or George upend the Cavaliers in May? Maybe. What about the Warriors in June? The future is an undiscovered country, but, I think we can fairly say “nah.” The Nets have the worst record in the league, and their pick will likely have a 25 percent chance of returning franchise-altering talent. The Celtics have a great coach, a solid group of players who can be moved as needed, and a realistic shot at the NBA Finals, all without relinquishing the Nets’ future draft picks. Still, the question lingers: If the Warriors weren’t so freaking good, would Ainge have pushed his stack to the middle of the table?

After surveying the board from the top of the CN Tower, Masai Ujiri, another rational actor, steered the Raptors toward action. The Drakes, once the clear challenger to Cavalier hegemony, have spent the past few weeks foundering. They’re now fourth in the East, behind the Cavs, Celtics, and the surging Wizards. Seeing the Cavaliers weakened by injury as the Raptors slid further down the standings, Masai went for it, acquiring Serge Ibaka to fill the cavernous hole at power forward and P.J. Tucker to stiffen the perimeter D.

In the West, where Golden State shows no signs of slackening, Houston’s deal for Lou Williams is the only move that could have an impact on who makes the Finals. The rest were housekeeping deals or hopeful moves for pieces that may or may not be keepers — Daryl Morey dealt K.J. McDaniels to the Nets for cap relief; the Mavericks semi-heisted Nerlens Noel from the Sixers; Sam Presti swapped Russ’s dancing partner Cam Payne, along with Joffrey Lauvergne and Anthony Morrow, for Taj Gibson and Dougie McBuckets — and then there was Sacramento’s irrational-actor trade of DeMarcus Cousins for a bag of walnuts and two pretzels.

All in all, an anticlimactic trade deadline. The Warriors and Cavaliers hold all the weaponry; no wonder teams are reluctant to shoot their shots. Check back in a couple of years.