And also the cable between Lithuania and Sweden:
https://www.theguardian.com/world/2024/nov/18/telecoms-cable...
replies(2):
https://www.theguardian.com/world/2024/nov/18/telecoms-cable...
https://www.theguardian.com/world/2024/nov/16/russian-spy-sh...
RU spent months gathering forces on the UA in Jan, Feb 2022. All the while, the US was publicly telling UA the odds of invasion were high.
Moving atoms at that scale doesn’t happen without lots of visible signs. The border nations already know what to look for.
And some border states have already built barriers at the border with RU, notably Poland.