> Shipping weapons to Ukraine to defend its sovereign territory is also a good. But it creates evil by escalating battlefield lethality and depending on the service (and often sacrifice) of brave Ukrainians.
Shipping those weapons does not create evil. The evil (Russian military aggression) is already there, the evil is responding to the weapons with escalation in an attempt to overwhelm to prevent defeat.
The proof is in not shipping the weapons: subjugation, slavery, for the Ukrainian people (quite possibly for generations to come). It can mean the complete wiping out of their culture, in the style of Tibet.
The weapons draw out a more dramatic response from the attacking evil, they do not create more evil; and they - ideally - prevent an even greater evil, which is the enslavement of the Ukrainian people if the war effort is lost. All the weapons do is pull some of the future suffering forward in time (you suffer more now, so your people hopefully suffer dramatically less later), however the trade, the potential upside, is obviously the possibility to achieve freedom and vanquish the aggressor. The aggressor creates all of the evil, all of the suffering, they're solely morally responsible for it. The weapons make a positive possible, the lack of said weapons guarantee only darkness. Putin's conquest effort isn't going to be stopped by peaceful protest (some authoritarians might bend for that under some circumstances, he won't).
The point is, the evil is already there. If you leave it alone (don't challenge it), you'll suffer more over a longer period of time. If you challenge it, you may suffer more short-term, however that challenge isn't creating any additional evil, it's creating the potential for good for the people of Ukraine. The suffering and evil can't be avoided, the only choice is whether you want to try to defeat it, or roll over and hand yourself over to its long-term chains.