Why would Ireland want to join NATO? Particularly as NATO has the Partnership for Peace where you can train to interoperate with NATO forces - which Ireland is already in. This gives Ireland the benefit of working with NATO without the obligation of having to defend Eastern Europe. So if Ireland feels it needs more air and sea assets (which I'd argue it does) then it's a natural to work with the UK, France the Netherlands and the US - and could always sign bilateral defence treaties with them and be a sort of semi-detached NATO member as it suits it.
Which is sort of what Sweden (and to a lesser extent Finland) already do. Nobody knows if NATO would defend them, Russia can't know they wouldn't. Particularly as Sweden is pretty vital to the defence of Norway.
Biting the hand that feeds IT
