It's amazing how hard communication can be! My simple sentence, "Finland is a NATO ally; but sure Canada makes sense too." has three interpretations - all reasonable IMHO:

1. cgh's: 'Finland is ok because they are in NATO; Canada, who in contrast are not in NATO, also makes sense.'

2. yours: 'Finland is an ally of NATO, not a member.'

3. mine: 'Canada may have 'close economic and cultural ties' (from the parent comment), but Finland is a member of the NATO alliance. Canada still makes sense (no comment on their NATO membership, which is a fact).'

I think some is context: In what I read, 'NATO ally' is a somewhat common term for members of NATO (an alliance, of course), and I instinctively used it. It's hard to remember that other people read their own materials.