The United States fired one missile. It hit its target, and there was trivial collateral damage.
Iran launched 15 missiles. Four (over 25 %) failed in flight. The remain eleven all missed their targets, causing collateral damage to a third party (Iraq) and wounding Iraqis.
Donald Trump set his red line a the death of an American, and he has not responded with further military action. Iran’s feeble response to our hit on Soleimani didn’t tempt him to ratchet up the fight. Rather, Trump’s restraint demonstrates the huge difference in power between the U.S. and Iran and the difference in our abilities to take a punch.
Elephants have thick skins, but if small insects become bothersome, elephants have the wherewithal to deal with them.