Every developed country in the world wants to revive its steel...

Every developed country in the world wants to revive its steel industry, especially the US. Its just so politically attractive. Even a short term dabble by China with tariffs and steel prices could have a tipping effect, as the governments of the world recommit to their steel industries. Chinas whole economy relies on cheap steel for manufacturing.
Just imagine the politicians of the US (or any major) announcing a rebacked green steel industry and that triggering a landslide of similar responses globally, Once committed to thats a 30 plus year problem for China.
Well placed countries like India would love the opportunity to usurp China.
I personally dont think they will risk tipping it, though they may test it.
As for impact on Australian iron ore, it doesnt matter where the steel is made, it needs IO. in my view discussion of steel tariffs tends to be accepting of high IO prices.
As to effect on GRR, because of its closeness with Shagang and its premium quality IO, whatever may come from China, GRR is perhaps the best placed to navigate it.
Fridays dip in GRR share price was illusory as to underlying sentiment. The sp was nicely up for the week and the indicators remain up. I think the news stories triggered kneejerk buyer hesitation and shook some of those closely held seller volumes to fall from the fruit tree. I personally think it will rebound as ppl digest the news.