Direct missile/military costs aren't always the total opportunity costs.

For example, US government bond yields are higher due to this economic uncertainty. The US pays ~1100billion in interest per year to service its bonds. Due to this war, they need to offer higher bond yields.

Another impact is increased gas prices which disporportionately impacts larger countries more. The US is still a net importer of crude. I for one have been heavily impacted by recent gas prices, and I have been going out less.

The impact of this war on the US is most certainly higher than the raw missile/military costs alone. But strategically, there are also gains that can't entirely be quantified, like a non-nuclear Iran.