How I can imagine it works: Amazon only provides the packaged software, the infra and the ops are officially driven by a 100% European company. AWS probably provides support, but they don't have the encryption keys not any access to the installation.
I guess the question then becomes: what happens if some future US government pressures Amazon to revoke the license. Unless and until there's a good answer to that, it'd still be better to develop something locally.
Sort of. AWS operates the China regions more or less like any other region, with oversight by the Chinese holding companies.
The EUSC will be more restricted, similar to GovCloud. Only EU citizens can access/operate it.
Specific example: an alarm fires for your service. If it’s in China, anyone on the team can go look at the logs. If it’s in GovCloud, only teammates who are American can look at the logs. In the EUSC, only Europeans can.
Whoops, the European company just got bought out by a US entity. Tough luck! [1]
Is this part of the spec? If not, it's as loose as a tent. And by "part of the spec" I mean "all your assets will be forcefully nationalized the second you or a parent company of yours becomes less than X% European owned", where X is well above 50.
As a rule of thumb, I wouldn't assume that any scenario you came up with on the spot was overlooked by an agency whose job it is to not overlook complex scenarios, let alone trivially simple ones.
To start with... states can and will absolutely block the sale of strategic national companies to foreign actors. But I'm sure you knew that.
The link shows that this isn't something I've come up with on the spot, it's literally happening today, and it's not being blocked. They can, yet will not, because scared of the US.