Your math is off. The missiles cost the US 832,000 USD each. With 23 misses that cost the american tax payer 19 million.. OUCH!
Can thus Trump decided to dispose of the old rocket shelf life which came to an end. Maybe that's why so many missiles had hit the target?
On the one hand, adults and children were killed with the help of chemical weapons, so retaliation had to come, and on the other hand geopolitical influence on the region. We should not look at what happened at the moment, but why it started and continues to this day with the participation of Russia and the United States. This is the protection of their interests and money does not play a role here.