Very obviously an anti-China thing.
Hilariously in practice its more anti-France than anti-China. Must be why Britain's so enthusiastically jumped aboard.
Unlikely, when it comes to military matters the UK and France work relatively well together. Notice how most of the French ire is directed at the US.
From the initial reports it's hard to say specifically what they're envisioning. Some early reports talked of buying US submarines, but that seems
really really unlikely. More likely it will be licensing of Royal Navy Astute-class tech, which includes a lot of tech the UK licenses from the US. So less direct tech transfer and more bringing Australia into the same arrangement the UK has had with the US. That would explain why the UK needed to be involved, though I'm sure Boris was happy to oblige!
Note that India is still conspicuously absent from this "Indo-Pacific" Asian NATO bs. I wonder what it's going to take to really get the Quad together, it'll be hard to contain China without flanking them in South Asia.
As I understand it India and Japan will conspicuously be present at the signing of the agreement in Washington.