Responsibility for war crimes attaches most to national governments along with the arms makers and military services they finance. The same is true of crimes against humanity.
Citizens become responsible with their governments if they are blind to what their governments are doing in their name in war crimes and crimes against humanity under codified international law.
“We didn’t know” is a form of denial and justification.
Complicity by silence Is the major causal factor at a population level of war crimes, crimes against peace and crimes against humanity.
Canada is a paradigm case.
Led by its Ministry of Foreign Affairs Canada has been complicit in and increases its role as an aider and abettor of US-led crimes against peace, war crimes and crimes against humanity as defined by international law in Libya, in Palestine, in Venezuela, in Haiti, in Yemen, in Ukraine, in Afghanistan, and arguably Iraq after invasion.
But our representatives at all levels seem silent on all of them unintentionally no doubt but not once known.