Russia has been using them against civilians as an invading force, and Ukraine wants these more advanced versions to use them against the incredibly entrenched Russian Army.
From wiki
“Russia launched a Tochka-U ballistic missile equipped with a cluster munition warhead at a crowded train station in the eastern city of Kramatorsk as hundreds of people were trying to leave the area. A detailed Human Rights Watch investigation found that the attack killed at least 58 civilians and injured over 100 others.
Is using them a war crime?
The use of cluster bombs itself does not violate international law, but using them against civilians can be a violation. As in any strike, determining a war crime requires looking at whether the target was legitimate and if precautions were taken to avoid civilian casualties.
“The part of international law where this starts playing [a role], though, is indiscriminate attacks targeting civilians,” Human Rights Watch’s associate arms director Mark Hiznay told The Associated Press news agency. “So that’s not necessarily related to the weapons, but the way the weapons are used.”
Its okay when we do it.
Can’t be a war crime if one is not a signatory as Russia, US, and Ukraine are not, however the use of them on civilian targets I imagine is,
The United States used cluster munitions in Iraq and Afghanistan on enemy positions.
Russia use their most sophisticate weapons almost exclusively on civilian infrastructure.