Let me put it to you in another context, it might help:

How would Pope Francis have dealt with the clergy sex abuse crisis, if he, instead of JPII, had been Pope in 1985?

Think about it.

Do we really know if Francis would have acted any different from JPII?

I don't think there is any way to know this.   We think Francis is the more more enlightened, humane and caring Pope on sex abuse, but then again,  Francis has the benefit of living through the errors of his predecessors, the times  they lived in, etc.

The same goes for American presidents.

That is, Obama wasn't president during 911, so we really can only guess what he would have done with Iraq and Iran.

It's quite easy to say Obama would  have pursued a gentle way of talking with the Middle East, avoiding all military conflict.   

But as with the Francis example, Obama had the advantage of not being president when such decisions were made.  

So no, I don't think much about an "Obama doctrine" as something to salute.