Last Call in Brussels

Sweden and Finland want to be in NATO. NATO mostly likes this idea, but Turkey is standing in the way. Which raises the obvious question:
Why is Turkey still in NATO?
In a very diplomatic column for Bloomberg, former NATO Supreme Commander James Stavridis writes:
Sweden has a high-tech military and produces the fifth-generation Saab Gripen fighters, which I was thrilled to have in our operations over Libya. The Finns, a nation of only five million, can put hundreds of thousands of well-trained and fully equipped ground combat forces in the field in a matter of weeks. We want them on our team.