Correct, this entire thing is just so US can build their domestic semiconductor industry again, because they see it as a national security threat and a long-term strategy. Semiconductors is important for the future of warfare, as things become ever more digitalized with drones, combat/prediction AI and autonomous weapons being developed.What are they trying to prevent? China's dominance in the China market that made 60% of their business? They're preventing nothing. This alliance is about helping the US do what it can't do on its own. It won't be preventing China from doing anything except making US allied governments, being their only customers, from paying more for a product China will be producing and selling cheaper in the world.
I don't think they'll succeed at getting everything they want though, all those semiconductor industries understand that US wants to harvest them and would likely drag their feet as much as they can, like TSMC building a plant in Arizona but the chip is only for 28nm.
It might take a while for their strategy to take result, but by then China would likely be insulated from sanctions, and those companies might have developed alternatives to Western IP to skirt around the sanctions and decrease the leverage US have on them.
Edit: Also they might want their competitors to lose their market share in China, to make it more sustainable for them to keep the operations by taking those lost market share.