Especially when a near-by country has a habit of being an aggressor:
* https://en.wikipedia.org/wiki/First_Chechen_War
* https://en.wikipedia.org/wiki/Second_Chechen_War
* https://en.wikipedia.org/wiki/Russo-Georgian_War
* https://en.wikipedia.org/wiki/Annexation_of_Crimea_by_the_Ru...
And let's not forget Malaysia Airlines Flight 17:
Some Islamic terrorists use terror to try to form a Qoqaz caliphate on Russian territory, and Russia fighting this development within their own borders is "being an aggressor". Meanwhile the US flies to to the other side of the world to invade Afghanistan and Iraq, which I suppose was a defensive action by its Department of Defense.
NATO is not just a self defence organisation. It's an offensive tool. NATO has gone into more offensive missions (at least 3) than truly defensive missions (literally zero - I don't count the invasion and occupation of Afghanistan as a defensive act).
For many members of NATO, the only existing military threat is within NATO itself (see: Turkey and some of its neighbors).
The truth is, NATO expanding is a great way for the West to force it's enemies to increase their defense spending and to lower the cost of offensive military interventions.
"How Russia Got So Big":
* https://www.youtube.com/watch?v=X1R_ycU_fS4
My ancestry is Slavic. You're going to go have a hard time convincing me not to worry about Russia.
As a westerner, that does sound pretty great- especially in the face of hostility from a glorified KGB thug like Putin.
If you neighbor wants to invade you and has done that already at least one in the past decade you might want a stronger ally than nobody. That is up to the country to decide. Though the cold war has shown that neither party wins in a climate of fear.
