It is double standard - and a show of ignorance if you continue with such statements.
The use of the A-bombs onto Imperial Japan IMO can be (reasoned with) - but it was clearly intended to kill off civilians en mass.
The US government form it's day one, continued for a hundred years the intentional destruction-killing of Red-Indian women, children and the old. Following the footsteps of the former colonial powers who's territory the USA had bought and/or conquered. And since then the USA never stopped killing civilians - just as all other warring nations.
The Vietnam war (since you had brought it up) wasn't abandoned due to military or financial issues - but because the US government had run out of excuses to justify the death of approx. 2 million Vietnamese civilians towards the world community and it's own population - (approx. a third killed by VC's, South and North-Vietnamese regulars).
It is meaningless to resort to "new US terms" such as collateral damage - to disguise the fact that the killing of civilians are taken intentionally/knowingly into account.
The Mai Lai massacre was an intentional killing spree of GI's towards Vietnamese civilians. Since then the US came up with the term collateral damage in order to differentiate intentional murder of civilians without targeting a valid or suspected military asset, and e.g. in contra of those civilians that perished due to a napalm strike onto a settlement were enemy troops were known or suspected to be.
It is also pointless to single out a specific party that supposedly or actually did start a war - any party involved in a war will automatically commit murder of civilians. This also applies to "indirect" assistance - such as presently in Ukraine - were e.g. US HIMARS missiles also kill Ukrainian civilians. Just because these Ukrainian civilians are presently living in Russian occupied/control areas doesn't make them Russian civilians either. Especially not, since the UN has not validated Putin's territory claims.
That is why any culture knowledgeable person knew - that the war in Afghanistan can't be won - since one would need to kill off more or less the entire civilian Afghan population, or endure military and civilian losses for 50 years and more, to hopefully fundamentally change a medieval cultured-society.
Right until now in world history, the winner solely decides about wrong and right (aka trials and punishment) - in case Russia should win, then Russia will certainly accuse every single government supporter of Ukraine as a war criminal. And Russia would even be right to do so - just as the West will do if we should ever win this ridiculous war.
So far there is no UN manifested law - that would excuse or justify the killing of civilians due to "preserving freedom"or "democracy". There is only an international law that defines a governments military right to defend ones national security and there are conventions that regulate the conduct of war. - where the killing of civilians is a total no-go for all sides and punishment/legal persecution is regulated according to international law.
If you can't face such simple facts - then all hope is lost on you. - and that is not a lie.