I am convinced of it, but I also believe that only GDP is not a sufficient indicator, things such as industrial production or R&D in the subject can be factors that complicate the thing.
In any case I am sure that a united European army would give Moscow cold sweats
My thoughts on this have not changed over the past twenty years, only my sense of urgency. I hope all of this will help push these ideas and policies forward.
It does and the actual wording is in my opinion a bit stronger in the EU guarantee, but I believe politically it's viewed as much weaker since the EU is fundamentally a economic/trade union and not a military one like NATO. That is to say, the EU could still exist without such a clause, but for NATO it's the entire reason for the organization to be.
EU: "obligation of aid and assistance by all the means in [the member state's] power"
NATO: "such action as [the member state] deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area"
Thing is though EU membership for Ukraine is still a ways off because there's still quite a lot of homework to do. A solution is needed now (better, five years ago), and that would mean a European defence treaty not limited to the EU. Also we want the UK to be part of it, anyway and, right now, while we're at it, let's make sure Canada is in.
until it’s tested, i’d guess states could say that “all the means” could be read with relation to trade and economics and other things governed by the EU
NATO's power lies not solely in its codified defense assurances, but in its integration. It might be a defense pact, but at its height of power, it is/was more than the sum of its members assistance.