In the short term it slightly reinforces the US's hand. I say 'slightly' because in fact the US already have power over ARM.
But longer term it creates a trend in which Armerican companies themselves will struggle in China. So what? Well, China will overtake the US so ultimately the US will have a disadvantage in the world's top market.
Edit: That's a key issue with the US's strategy with China, which seems to be focused on the short term (One might argue that they did the same mistake in Iraq in Afghanistan...) The point is that relations with China are a long game and China certainly plays a long game. The US need a long term plan and to accept that they cannot keep the top spot indefinitely.
But longer term it creates a trend in which Armerican companies themselves will struggle in China. So what? Well, China will overtake the US so ultimately the US will have a disadvantage in the world's top market.
Edit: That's a key issue with the US's strategy with China, which seems to be focused on the short term (One might argue that they did the same mistake in Iraq in Afghanistan...) The point is that relations with China are a long game and China certainly plays a long game. The US need a long term plan and to accept that they cannot keep the top spot indefinitely.