1. We have a large homgoneous market where you can build a product and it’s expected it can succeed for hundreds of millions of Americans
2. EU is the easiest second market, and another step change of hundreds of millions of customers in a somewhat unified market
3. there’s not an easy 3rd economy that replaces EUs wealth, population, and comfort with English + technology
When we piss everyone off in the EU tech company growth gets kneecapped and limited to US / Canada. Theres not an easy market to expand to without much deeper focus on that specific market and its needs, for much fewer returns.
Europe will buy LNG from Canada instead of the US, and continue to purchase imports from China. I agree though that a strong EU is needed, in part to defend against the US, as well as Russia (until the Russian economy reaches failure). CATL is currently building the largest battery factory in Europe in Spain.
Software also has the potential to be made by forking open source projects. That Canonical Ltd. (London) has Ubuntu is already a decent foundation, a wheel that probably doesn't need to be fully re-invented.
* ironically, one of my hobby-hills on green energy is that I have noticed that a genuinely global electrical grid fat enough to get resistance down to 1 Ω the long way around, would only cost a few hundred billion in aluminium. Currently only China makes enough to consider it, but still, the BOM for such a project is much less than the price of all the manpower needed for the last 100 miles.