From what I understand the Iranian blockade took ship traffic from 180-200 ships a day to somewhere around 10. This will take it from 10 to 0. I don't really see this being a massive disadvantage for Iran (not being rampant capitalists the money is nice but they're pretty self sufficient and I imagine Russia and China will dip their hands in their pockets to help). It will keep up the international pressure on USA due to rising oil prices and loss in supply and lack of fertiliser shipments etc. so personally I'm not convinced this is a smart play in the slightest. Think it makes Trump look like a war mongering dumbass even more and doesn't really alter Iran's strategy or strengths.