Those of us academics who teach about the factors that influence public policy can find nothing more powerful than history.
Policymaking starts with what is. How we got to where we are begins an endless quarrel, with each participant able to cite a cluster of economic, social, and personal elements and events to explain a favorite view of what caused what. 
There is no shortage of heroes and villains to assemble in whatever scenario you favor. The problem is, however, that a bright first year history student can assemble another collection with a different list of elements and personalities, or a different weighting given to each.
It's great fun to put together one or another fanciful  explanation of history, but it doesn't solve the problem of how to get from here to something better. 
You don't like right wing Republicans? Start with Henry Cabot Lodge (grandfather of his namesake, the US Ambassador to UN and South Vietnam), who led the Senate in opposing US membership in the League of Nations.
You don't like Europeans? Add to Lodge the British and French who demanded extensive reparations from the Germans after World War I, even though the Germans weren't any more responsible than them for the war.
Both streams of devils (Americans and Europeans) contributed to what became World War II, the Holocaust, the end of Empires, and all the stuff we have to deal with today, i.e., Israel, and Muslims who have streamed out of former colonies in the Middle East and Africa, who cause us problems at airports and the recent miserable weekend of events in Paris.
If none of that happened, it's likely that our parents would not have met one another and we wouldn't be here having to sort out the problems, figure out what caused what, and what we might do.
However we like to blame our various adversaries for where we are, we can't move backward.
Americans who are dismayed by their country's miserable social indicators can blame the colonists for putting the country on the cultural road of opposing taxes and government programs. "No taxation without representation" was a great slogan for middle class colonists and their successors. Yet the colonial activists who started this stream of public policy overlooked the character of the British Parliament as one of the most decent governments then in existence, the lack of representation experienced by almost all the British, and the use of those taxes to defend the American colonists in the recent war against France and its Indian allies.
Since the 1930s Americans have wrestled with their anti-government culture, and have made considerable progress toward what other governments provide their people.
Yet those who celebrate the Tea Party of 1771 continue to flex their muscles, and do what they can to move backward.
There is no shortage of Jewish leftists who condemn Israel for being imperfect.
Imperfect it is. However, the insistence on erasing what exists and starting somewhere else is nothing more than a recipe for frustration.
A point made by both sides in the Oslo negotiations (and one of the several successes of that process that is popular to blame for not solving everything) is to avoid the endless quarrel of how we got where we are, and who is to blame. 
Among the lessons, which many will not like, is that it is essential to accept almost all of the "settlements."
And Europeans must accept all those Muslims, and most likely more who are still coming.
Americans must accept a lot of unpleasantness that they have gotten themselves into, including a huge underclass prone to early sex and violence, all those guns, and who knows how many millions of illegal immigrants.
What to do? 
Ah. That's tougher than spinning historical explanations and blaming someone else for where we are.
Three prime rules in my book are
1. Don't make things worse.
Here we can learn something from history. Horror stories from the past and not so distant past (i.e., ISIS) can teach us what to avoid.
The abominations associated with Charlie Hebdo and the Kosher market should sensitize us to the knotty problems around religion, including how to find a way through respect for religion and competing values that include an essential right to criticize.
Palestinians might learn (they are showing no signs of it) from errors their side made in 1967, 2000, and 2008. Settlements built or expanded since then are not likely to disappear. Israelis are wrestling between those wanting to expand settlements, and those wanting to give the Palestinians yet another chance to accept what exists.
2. Start small. Incrementalism is more likely to move forward than any grand steps.
If you accept #1 and #2, you may begin by telling Barack Obama, John Kerry, Martin Indyk, and their friends in JStreet. They're waiting for the wrong bus. They might know better how to deal with their most prominent adversaries among the Republicans, who are itching to cut taxes, shrink government, and make things worse for Americans.
3. All of the above is based on the importance of probabilities. The goal is to identify policies likely to make things better, and to avoid those likely to make things worse. Success is likely to come in small steps, crafted to avoid offense to those with power. 
We can't say for certain that there isn't a true Messiah or political genius out there with a grand design for what to do and how to accomplish it.
But the record of history and a sensitivity to probabilities tells us that it ain't likely.