Others move deep into the West Bank to claim land for Jews, out of religious fervor and/or a desire to see more or all of the West Bank absorbed into Israel. While Israel officially forbids this and often evicts these settlers, many are still able to take root.

The simple version is that violence has become the status quo and that trying for peace is risky, so leaders on both ends seem to believe that managing the violence is preferable, while the Israeli and Palestinian publics show less and less interest in pressuring their leaders to take risks for peace.

That sense of Palestinian hopelessness and distrust in Israel and the peace process has been a major contributor to violence in recent years.

"We don't have a partner for peace."

9 questions about the Israel-Palestine conflict you were too embarrassed to ask

And as Ukraine's conflict grows deeper, the reputation of the U.S. as the ultimate arbiter of the international system has yet again suffered. As with Iraq, Ukraine is a case of a violent disintegration, and there is not much Washington can do about that.

But the potential economic effects of the likely Ukrainian collapse will be devastating on Russia, even if Moscow manages to not get involved in a direct military confrontation with Kiev. The deeper Ukraine moves into a civil war, the more costly it will ultimately be for Russia to rebuild what is left of Ukraine's eastern regions. As Ukraine's largest neighbor and the international supporter of the eastern fighters, Russia won't be able to step aside.

f the international community summons the will to pressure Kiev, Moscow can be helpful in pressuring Donetsk and Luhansk to negotiate a cease-fire.

Andrei Tsygankov is professor of international relations and political science at San Francisco State University. His forthcoming book is "The Strong State in Russia: Development and Crisis" (Oxford, 2014).