The White House recently identified semiconductors as an essential product critical to US national security [1]. These actions by the US and allies to onshore fabs is part of the adjustment to defuse a supply chain risk caused by potential future actions by China.
During the Cold War, both sides used strategic release of classified information on capabilities to notify the war planners on the other side in order to prevent miscalculations that could lead to a nuclear exchange. This is common knowledge and a good tactic to tamper escalation. It would be extremely irresponsible to surprise a nuclear peer with new capabilities.
[1] https://www.whitehouse.gov/briefing-room/statements-releases...
I’m not sure I buy your reasoning though. I don’t understand how effective blocking the use of US technology by SMIC will be given the propensity for IP theft, so I don’t see how it furthers the goal of preventing China from becoming self-sufficient. Nor would I really agree with the assumption that they are not already self-sufficient.
The semiconductor industry is extremely R&D heavy. You can't just steal your way into success. It is also heavily dependend on a global network of specialized suppliers and is one of the most complex supply chains on earth.
Even Chinese media says that they are not yet self sufficient. They predict that SMIC will become able to produce 28nm and above using only domestic inputs by the end of 2022, but that's just ability and doesn't factor in manufacturing scale to handle the corresponding demand.
Making 14nm fully domestic takes a bit longer -- maybe 2 years more. Chinese media and experts say that if they scale up 14nm and above, then that satisfies 70% of the demand.
To go further than about 7nm you need EUV lithography, which only has 1 supplier in the world, and the US is blocking that. How long it takes for China to independently develop EUV is unknown. Universities have made small breakthroughs in subfields here and there but they're still far away from the full solution.
For most military applications, 28nm process is comfortably sufficient - USAF 5th generation aircraft were designed and flying before 28nm.
I’m not convinced that there is any real need right now for <14nm process besides striving for market share. Market share which is itself reorganizing around new ISAs. EUV is a (amazingly clever) Rube-Goldberg machine.
Except they increasingly fly their fighter jets in Taiwan's airspace. And regularly engage in deadly border disputes with India. And continue to conduct cyberwarfare.
https://www.bbc.com/news/world-asia-58794094
https://en.wikipedia.org/wiki/2020%E2%80%932021_China%E2%80%...
https://independentaustralia.net/politics/politics-display/l...
Except that the border dispute with India was caused by the British, who randomly drew some borders somewhere that parties then later disagree with. India also has border disputes with non-China neighbors. China already tried to solve this diplomatically, for example by trading areas that India claims but are defacto China-controlled and vice versa, but India refused all deals so far because they want to claim in all.
Do note that China (PRC) has already given up land in the past as part of diplomatic deals. Check Vladivostok. Check the whole of Mongolia.
Western coverage of China’s border conflicts are extremely distorted. In the ASEAN summit, southeast asian nations are upgrading strategic ties with China.
https://www.france24.com/en/video/20211028-asean-summit-sout...
Many countries are worried about AUKUS. Malaysia planed China consultations as anxiety simmers over defence pact.
https://amp.scmp.com/week-asia/economics/article/3149713/mal...