and one reason we don't do anything nasty to Iran is that by mining or blocking the Straits of Hormuz they could cripple the world's economy very very quickly.
As for "Why are we still allowing soldiers to be killed with Iranian weapons? One of our guys is killed by an i.e.d=One of their power plants, hard-to-replace bridges becomes a crater."
It's because we supply weapons to the rest of the world, too.
We didn't bomb hell out of France when the Exocets hit our ships, we don't bomb Russia when our troops are shot with Kalashnikovs. Time to grow up.