Macron is just doing what France always does: try to act important even though they are completely irrelevant compared to the US. France, and Macron, are incredibly anti-Muslim because of domestic pressure from far-right parties who are catching up to him.
Almost all the oil/gas that passes through SoH goes to Asia. Western oil imports do not go through the SoH. As for Western allies like Japan and South Korea, the West will simply divert the oil they currently sell to China to go to them instead. There may be penalty clauses and wartime exemptions in the contracts, but those are details. Once again, the squeeze will be on China. China's economy is already on edge and the last thing they will appreciate is this 'gift' from Iran.
As for spare capacity, Saudi Arabia alone has spare oil capacity of 5 million bpd which can be ramped up within days. Keep in mind that Saudi Arabia has export terminals on both coasts. The US has strategic reserves but they are for domestic use, not export. However, with those reserves in play, the US will have more freedom to put the brakes on global oil prices since it is the largest exporter of oil. Between Saudi Arabia and the US strategic reserves, we have almost 10 million bpd of extra oil available within days.
So, bottom line, yes there will be global impact but the brunt of it will be on China and non-Western allies. Everybody, including the West, will be impacted by the rise in oil/gas prices but the West will ride it out much easier compared to the rest of the world.
If the intent is to punish the West, then this weapon is pointing the wrong way.
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