War with Iran

As you can see in my last post, Iran says it will shut down the Strait of Hormuz, I keep on getting different ideas on what could happen, we know that the have the Sunburst Missile, which flies low and erratic flight path, they say it is too low to get shot down by the US Navy's Phalanx Close-In Weapon System.  One of these missile could cripple or even sink one of our ships.  But Iran may only be able to shut it down for a day or so too.  Or a very long time.  Also China has said that they will help Iran if the West attacks.  Russia may help too.  World War 3 may be about to start. This could sent oil skyrocketing.
UPDATE: I am hearing that the US navy could sink all or most of the ships in the Iranian Navy, but Iran could use small inflatable craft to sink ships, including oil tankers.