I think you have some confusion about the role of the Linux Foundation in relation to the kernel. They provide financial, organisational, and infrastructural support and neither own nor control its development.
Linus is the BDFL and lead maintainer and if he wanted to move the kernel development anywhere else he could do so, but Linus Torvalds has stated that he personally agrees with them.
That is not the US controlling him, it is his own decision. Moreover he has dual citizenship and could renounce his US citizenship if he chose. When Greg takes over maintainership things may be different.
Why should Linus renounce US citizenship, not finnish? He is living with family in Oregon for 20+ years.
This is my main point here - not much things connecting Linus and Linux to EU. In question of US and EU tensions I am not really sure US citizen BDFL will party with EU, also because companies who spend money and contribute to kernel are located in US mainly.