Tom Friedman, who has an equal amount of knowledge in Foreign Affairs...especially in that region...I've posted his thoughts wrt Israel, Palestinians and Iran...all need to have "regime changes" in order for peace to prevail...as for Ukraine and Russia...Putin WANTS/NEEDS Ukraine under Russian control...he'll never stop...certainly didn't after Crimea, which Prof. Mearsheimer seems to have forgotten...therefore, it's up to the Ukrainians and I believe, like the No. Vietnamese...they'll never stop seeking their own control...and we'll be with them...for many more reasons...until they get there. (so will the NATO countries).