Let's unpack it then.
You've stated:
>"Mostly from Australia and Chile" seems like the opposite of baggage, that sounds like about the best you could hope for in a global commodity, so many of which come from unstable regions, conflict regions, or outright adversaries.
So let's break it down with some facts (all easily searchable.)
(1) The graph states that Australia is the largest producer of Lithium, and states that of their exports, 90% goes to China.
(2) Australia exports the majority of its lithium. (https://www.abs.gov.au/articles/insights-australian-exports-...)
(3) Lithium ion batteries are currently reliant on Cobalt for their cathode.
(4) The DRC (Congo) is the largest producer of Cobalt, then Indonesia, then Russia.
>"seems like the opposite of baggage ... unstable regions, conflict regions, or outright adversaries"
From (1) and (2) we can see that the world is dependent on China for the only viable battery option for a range of modern applications. Thus the claim that this isn't baggage is not supported. Secondly China is also considered an adversary of the USA, by the USA. Thirdly the claim that this does not involve unstable/conflict regions is also not supported due to (3) and (4).
Part two: you've also stated the below:
>"Building new Na-ion capacity outside China" is probably even harder than "building new li-ion capacity outside China."
While this is a baseless comment, let's look at it anyway:
(5) The article is specifically about the commencement of mass production of Na batteries in the USA.
That already refutes the core premise of your statement, but let's follow it further.
(6) The article notes that unlike Li batteries, the materials are trivially sourced domestically.
That's an important difference from Li batteries, and significantly boosts the viability of competitive production in the USA (and other countries outside of China).