Putting aside the Houthis are dictators so aren’t in any position to lecture on ethics… for their own state a government can impose sanctions. If they randomly attack the property of other states that’s called an act of war and terrorism. If the current dictators of Yemen don’t want to listen, they will face the consequences of billons of dollars of damage to their infrastructure and deaths of their citizens.. And that’s with a tiny tiny fraction of the firepower available to the US who are fighting with one hand and another four fingers behind their back. Great restraint while the Houthis behave like Don Quixote.