My understanding of the 2018 CLOUD act is that a US headquartered cloud vendor must hand over subpoenaed customer data even if the datacentre is outside the USA.
https://www.dlapiper.com/en/us/insights/publications/2018/04...
https://www.dlapiper.com/en/us/insights/publications/2018/04...
Disclaimer: I work in Azure but not on this, so my info may be wrong.