not supplying them to Ukraine gives russia an advantage, thus being against the US supplying them to Ukraine is de-facto a pro-russian stance.

I strongly disagree with you here. I’m not against providing any weapons to Ukraine, I just believe there are better options than cluster munitions — options which won’t still be killing civilians in the decades to come. I don’t believe that cluster munitions are in any way essential to Ukraine’s defence.

Ukraine and its allies can’t do anything (short of surrendering, which I certainly don’t advocate) to stop Russia’s use of them, and there will be long-term consequences. But that doesn’t make it a good — or even neutral — idea to add on additional long-term consequences. The more unexploded ordinance, the more danger to residents in the future.