No, neither the USA or UK are really independent on this program. They are mutually dependent on each other.
The USA does have all of the technical data packages so in theory we could probably get domestic suppliers to make the components we currently get from the UK but it would take several years. The reverse isn't true, though. The UK simply no longer has the capacity to support such a complex program on their own. They sacrificed their defense industry years ago and accepted dependence on the USA so that they could fund social programs.
I'm not suggesting that the UK attempts to make all the parts that are made in partner countries, merely that they have access to the information required to do so.
If that's the case they maybe they would be able to help the other partner countries develop the parts that they would otherwise require America to make.
The USA does have all of the technical data packages so in theory we could probably get domestic suppliers to make the components we currently get from the UK but it would take several years. The reverse isn't true, though. The UK simply no longer has the capacity to support such a complex program on their own. They sacrificed their defense industry years ago and accepted dependence on the USA so that they could fund social programs.