This is good news for, and from, the Balkans, even if many Croats don't see it that way and are taking to the streets. To them, the man who spearheaded the 1995 drive to crush the Serb rebellion in the Krajina region was a hero - end of story. They are not interested in discussing whether Operation Storm needed to involve killing hundreds of Serb civilians and expelling thousands from their homes.
There will always be Serbs, Croats, Bosnians and Kosovars with that tunnel vision. But in time, most Croats will come to see that the arrest has lifted a Sword of Damocles over their country, for although Brusselsopened accession talks in October with Croatia after Ms Del Ponte declared Croatia was co-operating with the tribunal, Zagreb got only an orange light. While the country's last major war crimes suspect remained at large, the accession process could have ground to a halt at any stage - and probably would have done. With Gotovina in custody, that scenario disappears.
But Gotovina's arrest has wider implications for the region, too, mainly as it will ratchet up pressure on Serbia to deliver its own last big fugitives - Radovan Karadzic and Ratko Mladic - whose roll call of atrocities makes Gotovina's alleged crimes pale in comparison.
Like Zagreb, Belgrade has claimed it has no idea where its suspects are hiding. In reality, the security services in both countries, out of control and operating to an independent agenda, have actively shielded suspects. In Croatia, the government finally grasped this nettle, and the imposition of effective control led to the tip-off that ended with Wednesday's arrest. The Serbs now need to tackle their own rogue security services if they are to get anywhere with locating their wanted men.
If that were to happen, and Messrs Mladic and Karadzic were to go to The Hague, it would mark an impressive conclusion to the tribunal's work. When it started work in 1993, the court was widely ridiculed. Since then, it has indicted 161 people, including the president of Serbia and the prime minister of Kosovo, and been far more successful in forcing all the components of the former Yugoslavia to hand over their leading suspects than anyone once imagined. Last week, only seven suspects remained at large. Now that there are only six, Ms Del Ponte is entitled to feel a degree of satisfaction. No, it is not mission accomplished. But it is getting there.