The International Criminal Court marked its 20th anniversary on Friday, with the Ukraine war giving the tribunal new impetus after two decades of criticism and controversy.
Since its founding Rome Statute entered into force on July 1, 2002, the world's only permanent war crimes court has had a poor record of just five convictions.
But The Hague-based ICC remains the court of last resort for grave charges such as genocide, crimes against humanity, war crimes and aggression, when member states are unable or unwilling to prosecute.
The ICC "is a pillar of the international legal system", the court's president, judge Piotr Hofmanski, said as he opened a gathering to celebrate two decades of the court's existence.
Russia's invasion of Ukraine and the subsequent ICC investigation into alleged war crimes have made the international community realise the importance of the rule of law, said ICC prosecutor Karim Khan.
"If we don't hold on to the law today, I think there is very little hope for anybody's tomorrow," Khan told AFP in an interview in May.
"That growing realisation has been rendered more acute because of the events of the 24th of February and the events in Ukraine -- and I think it's long overdue."
Speaking at Friday's ceremony, Khan said the ICC's establishment 20 years ago "was a tremendous achievement".
"The prayer must also be that, in twenty years to come, many may see a world better, safer and most just than it is for so many of our fellow brothers and sisters today."
- 'Lofty goals' -
The court said the event was "an occasion for reflections on how well the ICC has met expectations".
But those expectations have always been high.
The ICC is the successor to the Nuremberg trials of Nazi war criminals, when the post-war international order sought an ideal of global justice.
Tribunals into the wars in the former Yugoslavia in the 1990s and the 1994 Rwandan genocide also laid the ground for a permanent court.
The Rome Statute was signed in 1998 and came into effect four years later, allowing the court to finally open its doors.
Yet since then, it has failed to snare any senior government leaders, and its five convictions so far have all been African rebels, including one former child soldier.
"Contemplating the ICC's legacy in light of its lofty goals, the results are negligible," Thijs Bouwknegt of the NIOD Institute for War, Holocaust and Genocide Studies told AFP.
It had high-profile failures, with ex-Ivory Coast president Laurent Gbagbo being cleared, former DR Congo vice president Jean-Pierre Bemba acquitted on appeal and Kenyan President Uhuru Kenyatta having charges dropped.
Just as damaging is the absence of key players.
The United States, which signed the Rome Statute in 2000 but never ratified it, has sometimes been actively hostile, at one point sanctioning the court over its Afghan probe.
China, Israel, Myanmar and Syria have also steered clear, along with Russia -- which even allegedly sent a spy posing as an intern to target the ICC's Ukraine probe.
- 'Recipe for Armageddon' -
But while there was "deservedly" criticism of the ICC, the court had made a "significant contribution", said Victoria Kerr of the Hague-based Asser Institute for International and European Law.
"The ICC is not a panacea, nor should its effectiveness be measured solely on its convictions," Kerr told AFP.
In recent years the court has sought to improve, with new probes into the Israeli-Palestinian conflict, Afghanistan, Myanmar, Venezuela and the Philippines.
Ukraine is now where the court has a chance to prove its credentials.
Khan said the recent backing of 43 states for the ICC's Ukraine probe was "not simply because of what's happening in Ukraine".
"When we view international law as an a la carte menu which states can pick and choose from... that is a recipe for Armageddon," he told AFP.