> If the radars that the USA uses are so great, then why don't Finland and Sweden purchase these systems instead of blocking almost all offshore wind farms?

Are you deliberately not trying to see the difference?

Early warning systems need all the help they can get when you only have 100km to your threats (ie. the baltic sea); when you have the entire Atlantic you don’t need that.

US early warning systems are great because they have 1000s of kilometers of space.

As other commenters have already pointed out to you, the Nordic countries do allow wind farms in:

    - Gulf of Bothnia (Sweden + Finland)
    - Kattegat (Sweden)
    - Noregian sea (Norway)