Do you really think that's true? What a wonderful deal for NATO. A nation sits on it's hands for decades and never lifts a finger, then suddenly when they need help, NATO is to risk their lives and treasure on their behalf simply because they've decided to grace NATO with their presence? NATO is an alliance of members who give something to get something- and nobody is going to agree to such a one-sided deal. Don't you play war-games? - they'd let you fry, then come in afterwards to do their own thing, under their own flag. For a while that area of land would be known as "the former Finland", then renamed "McFunland" under new management.
