Goals from Dele Alli and Harry Kane, the latter from the penalty spot, condemned the Gunners to defeat and further complicated their pursuit of Champions League qualification.
The hosts dominated the first half but struggled to stay composed in big moments, missing a couple of big chances before the break.
But whereas Arsenal might previously have rallied to overpower their neighbours, Spurs stayed strong and Alli capitalised on sloppy defending to stab home from close range.
Moments later Kane had won a spot-kick, converting it himself, to double the lead.
And that was that for an Arsenal team lacking in fight, cohesion and quality.
But what did we learn? Here are five things....
1. Spurs show steel to get over missed chances
Tottenham were the better side in the first half and really should have taken the lead.
Dele Alli looked for all the world as if he would head the hosts in front but managed to only guide it wide of the post with no keeper to beat.
Christian Eriksen's miss minutes later was possibly worse, side-footing over on the volley when all he needed to do was keep the ball down to break the deadlock and give his side the lead that their superiority had deserved.
When Arsenal eventually woke up and came into the game, those missed chances fed into the uneasiness that Spurs were going to do a Spurs, that they were on the brink of tossing away their title hopes in the final north London derby to be held in this historic stadium.
But when Alli scrambled home a second-half opener, it triggered a second within minutes. The first goal was met with the roar of relief, the second with joy.
Tottenham had showed a mental fortitude they'd been accused of lacking, shrugging off some blown opportunities to put their arch rivals to bed.
It hasn't been the case for a long time, but Tottenham are the better side than Arsenal and this season they will have the league position to prove it.
2. The balance of power does seem to have shifted in north London
Thierry Henry made something of a stir in the run-up to this game by suggesting that Alexis Sanchez is the only Arsenal player that could get into the Tottenham team.
Given Henry’s legendary contribution to the Gunners over the years it was a headline-worthy statement but not by any means a fanciful one, and watching today you’d argue he was even perhaps a little generous to his former club in his assessment. It’s not an exaggeration to say that Tottenham are now, undoubtedly, the superior side.
Player-for-player they had the upper hand across the board today while the difference in the dugout may be even more significant. Every home player won his one-on-one battle this afternoon as the hosts dominated from the outset.
While Arsene Wenger may be right in terms of how far Spurs still have to go as a club with a tricky transition to a new stadium to come, watching the two teams go to work on the same pitch it’s hard not to come to the conclusion that the balance of power really has shifted.
3. It's the north London derby - but not as you know it
Not only did Tottenham outplay Arsenal in the north London derby, but they will now finish above Arsenal in the league.
That is enough to make this into an unusual renewal of this rivalry, which at times didn't even feel like one, such was the lack of animosity.
Indeed, the Gunners will depart White Hart Lane for the final time with a whimper. There was little fight, little bluster, little anything from them. Not so much as a booking for their troubles until the 70th minute and the closest they came to showing they cared was Danny Welbeck's tame spat with Toby Alderweireld.
Such a lack of, well, anything from Arsenal was not the sort of performance Arsene Wenger needed with his job under pressure.
4. Alli has added goals to his guile
Dele Alli’s all-important second-half goal was his 17th of the season, an absolutely remarkable achievement for a player who occasionally lacked poise in front of goal last year. He is comfortably the highest-scoring midfielder in the league and his (albeit scuffed) finish means he has now scored as many times as Zlatan Ibrahimovic this season.
At the tender age of 21, Alli has already reached a level where he is one of Tottenham’s most likely goal-threats no matter what position he plays in. In the enforced absence of Mousa Dembélé, Alli played in a slightly deeper role with Heung Min-Son and Christian Eriksen positioned further forward alongside Harry Kane, and yet it was still Alli who seized the initiative and broke the deadlock.
It is hard not to get carried away with a young English talent when he is playing at this level week-in, week-out. But the Tottenham man is on the brink of becoming something spectacular and Tottenham's future should be built around his unique talents.
5. Missing: Mesut Ozil
The German playmaker was included in the starting lineup but you wouldn't have known it from watching the game.
Another invisible display from the former Real Madrid man does little to endear him to the fans who are already angered by his refusal to sign a new deal.
Ozil's supporters, rabid as they are, point to the little things he does. Here they were so little as to be microscopic, either that or simply non-existent.
It was another big game where Ozil has been a non-entity, and it's the game that would hurt fans the most.