As far as I can see from research there have been judicial cases against leaders of 15 different countries between 2000 - 2020. (9 of them in Africa). Between 2020 - 2024 I have found 11 more. My list may well not be exhaustive. My point is that this is not isolated behaviour. It is becoming more & more prevalent. The increase starts to become much more evident in 1993 with the Jugoslavian war tribunals. It is becoming learned behaviour by unscrupulous & greedy leaders. They know that they can get away with it.
2000 -2020 - East Timor, Sierra Leone, Italy, Cambodia, Peru, Congo, Sudan, Libya, Kenya, Tunisia, Egypt, Guatemala, Chad, Ivory Coast, Kosovo.
2020 - 2024 - Croatia, Argentina, France, Israel, Italy, Malaysia, South Africa, South Korea, Pakistan, Russia, USA.
To my mind this pattern, which seems to be endemic, matters because of what is now happening in Ukraine, Gaza & the West Bank & possibly even more crucial, the American presidential elections. Putin, Netenyahu & Trump, if he is elected, are not leaders intelligent & caring people want to be in charge of wealthy & powerful countries.
The problem is that although there is International law & there are International courts, bringing transgressors to justice isn't easy. For a start you have to be able to get the leaders into an International courtroom. They aren't going to volunteer, so they have to be extradited if there is regime change, or they have to be forcibly brought to court. They can be tried in absentia, but not sure that really puts them off.
Then there is the difficulty posed by gathering a verifiable evidential trail & credible witnesses prepared to risk testifying. In addition, the Prosecutors & Judges face intimidation & worse from supporters of the criminals. It takes courage to go against incredibly powerful & usually wealthy men, (mostly). Not only the people trying to enforce the law themselves are at risk, but also their families. Not sure I would put my head above the parapet.
It's a quagmire. Law is important, but it does have to be enforceable & have consequences for the perpetrator. Especially when it involves death, destruction, genocide, starvation, crimes against human rights & humanity & complete corruption.
The really startling thing is that there are so many men, (usually), prepared to behave in this inhumane way to retain power & accumulate obscene levels of wealth.
We need to find a solution that works.