Depends on what kind of Brits you mean. You think the Brits of today would have been behind the Balfour Declaration, especially given their attitude towards “settlements” today?
Not sure quite what you’re getting at, specifically what part of the Balfour declaration you’re referring to, and I am not an expert on the particulars of same.
Brits have very little, if any love for Jews. It’s...genetic or something. They are suppressed anti-Semites, IMHO. What they dislike about Jews, I do not know, but I’d assume it’s kind of the Euro thing, that most of the various nationalities seem to think that Jews are such good businessmen that they must be taking advantage of others. Envy, in other words. Born, perhaps, of the generally rigid class structure of most Euro societies. If you’re born poor, you die poor, and how dare you aspire upwards, it makes everyone else look bad.
They can have it. But regardless of the nuances, Brits are very widely anti-Semitic (which makes no sense because the Arabs they love are Semites) and so I conclude they are by and large anti-Jew. I believe most Jews understand the antipathy and in a chagrined way, accept this on the part of the Brits like they get it from most other groups.