U.S. President Barack Obama's speech in Jerusalem was without question the strongest ever made by a senior American politician on the Israeli-Palestinian conflict. It was plainly designed to speak directly to the Israeli and Palestinian peoples over the heads of their political leaderships. It was an exercise in public diplomacy par excellence, intended to change the tone and atmosphere, and public perceptions of Obama himself, presumably as an adjunct to actual diplomatic efforts to lay the groundwork for eventually resuming negotiations.

The psychological, communication and political skill that was marshaled to give the speech its maximum impact with public opinion was quite extraordinary, and stands in contrast to some miscalculations Obama made about Israeli and Palestinian perceptions during his first term. By systematically downplaying expectations for his trip, Obama made the power of his speech and the boldness of some of the language and positions he staked out -- particularly regarding the realities Palestinians face under Israeli occupation -- surprising and therefore all the more striking.

Obama made the first day of his trip an extended exercise in telling the Israeli public everything it could possibly want to hear from an American president, ranging from "undying bonds of friendship" to robust reiterations of security commitment and a much yearned-for acknowledgment of the long Jewish history in the land. In retrospect, it's clear that what looked like public outreach bordering on pandering was, in fact, designed to transform Israeli perceptions of Obama himself in order to prepare them for some of the hard truths he was preparing to deliver the next day.

What Obama has done is to reassure and challenge Israelis and Palestinians alike. To Israelis, he reiterated America's undying support and commitment to Israel's security. But he confronted them with the fact that "the only way for Israel to endure and thrive as a Jewish and democratic state is through the realization of an independent and viable Palestine." He reassured Palestinians that the United States is not walking away from the effort to create an independent Palestinian state. But he told them they must recognize that "Israel will be a Jewish state" and challenged them, and the rest of the Arab world, to begin to normalize their relations with Israel.

From a Palestinian point of view, it was already highly significant that Obama was not just going to Israel but also Ramallah and Bethlehem for significant talks with both President Mahmoud Abbas and Prime Minister Salam Fayyad. This communicated several important messages: that the Palestinians are still an important factor in the equation, and that they have a leadership, including both Abbas and Fayyad, that is to be engaged with seriously. And by specifically and repeatedly citing the Palestinian Authority's institution-building and security measures led by Fayyad, Obama was sending a clear signal that he wants to continue to deal with the present Palestinian prime minister, who has been under considerable political pressure in recent months.

But the speech itself gave the Palestinians a much deeper recognition, and one they've never fully received from American officials in the past. Obama went to enormous lengths to humanize the Palestinians, comparing them to his own daughters and to the young people of Israel. He did not simply reiterate the American commitment to a two-state solution, he spoke of the "Palestinian people's right to ... justice." This can only be seen as a clear, albeit implicit statement that the status quo of occupation is an ongoing injustice. He challenged his Israeli audience to "look at the world through their [Palestinian] eyes," which speaks to the Palestinian need to be acknowledged as fully equal human beings by the Israelis. And Obama admonished Israel that "neither occupation nor expulsion is the answer," directly addressing the two main Palestinian historical traumas and ongoing anxieties.

The effectiveness of Obama's careful political and psychological preparation for these unprecedented statements with his Israeli audience was demonstrated by the sustained, and otherwise unimaginable, applause he received for almost all these remarks. He clearly went a long way in assuaging Israeli skepticism. Palestinians will be harder to win over, as they require more than words given the onerous conditions of the occupation and their repeated disappointment with successive American governments, and in particular with Obama's first term.

There is no question that Obama's extraordinary speech will have a significant impact on how he is perceived by both Israelis and Palestinians, although how long that lasts and what kind of political or diplomatic impact it will have very much remains to be seen.

One of the more remarkable aspects of this outreach was how it stood in stark contrast to his diplomacy with political leaders. He explicitly told the Israeli and Palestinian publics that he was directly addressing them, not only over the heads of their political leaders, but in order to challenge them to confront those leaders. If entrenched politicians have become an obstacle to peace -- and they may indeed have -- why not go around them? "Political leaders will not take risks if the people do not demand that they do," he said, adding, "You must create the change that you want to see."

Essentially, Obama was saying, "If you like what you've heard today, you have to help me because your leaders aren't going to cooperate without significant pressure from you. I can't do this alone, as I discovered in my first term. I need your help."

In his first term, Obama essentially tried dealing with the leaderships directly and barely engaging with the Israeli or Palestinian publics. One subliminal message of his speech might be that he discovered this approach is a dead end, and that to get beyond the present impasse requires more robust public engagement. Whether he's done enough to promote or sustain that will have to remain to be seen.

Diplomacy without sufficient outreach may have proven to be a failure in Obama's first term. But this kind of bravura performance of public diplomacy will have to be backed up with significant real diplomacy or it may be remembered as yet another inspiring Obama Middle East speech that ultimately produces more disappointment than tangible achievement. Still, if Obama was primarily trying to change the tone and the atmosphere in the region, and the way he is perceived by ordinary Israelis and Palestinians, it's hard to imagine how he could have been more effective than he has been over the past couple of days.