Historical record does not bode well for UK defending anyone when not directly threatened.

It took serious damage to imports and an invasion for them to move during the last World War.

That's nonsense, but even if we take as true for a moment;

The argument here is they don't want to buy our weapons because we might decide to stop selling to them. Do you really see that as even vaguely likely in a war against Russia?

We want to make our own weapons because depending on someone else can be more costly. But some parties in UK do have worrying ties to Russia (reform uk and conservatives). I mean who would have thought that Republicans in US would be 3rd best allies of Putin, right after China and North Korea

1.those are not the only options, far from it. If EU buys from 3rd party, that party gets to dictate what we can do with those weapons. How long have EU countries been asking US to allow them to transfer F-16, longer ranged artillery, missiles, MBT,... to Ukraine? Also, lets remember that UK has prevented shipping vaccine manufactured there to 3rd countries, even when some other country paid for it already. EU did not do that.

2. Thank you for confirming our fears. We decide not to buy something for you and now you go full crybaby and deny Ukrain help. Yes, you guys sound like totally dependable.

3. It's not isolationist and we do want (or should want to) cooperate with you, but Eu has just learnt what happens if you outsource your own defense and US elects idiot for the 2nd time. And lets not forget that you have political party on the rise, (Reform UK), that seems to be a bit too friendly with Trump, Farage supposedly received money from RT (russ sponsored Tv) in 2022. One of your previous PMs (Boris Johnson) had appointed Russian oligarch as Lord and is said to have ditched his own security to party with Russian intelligence officers while he was in office. So, if eu and russia come to blows, whos side will UK be on? Depends on what party is in government.