We don’t know what will happen. After the high drama of Tahrir Square it seemed certain for a moment that Hosni Mubarak would depart, but he showed formidable resilience in clinging to power.

But if detailed prognostication is foolish and presumptuous, some things can be said with confidence. No regime that follows Mubarak’s in Cairo is likely to be as friendly to Washington. More generally, American policy is unraveling throughout the Middle East, and far beyond. We are witnessing an historic eclipse of US power. Despite the difficulties American forces have lately experienced — history might have taught that there are rarely short sharp victories to be won in Afghanistan or Iraq — and for all the economic challenge from Asia, the United States remains overwhelmingly the most powerful country in the world, or in history. In military might it overshadows most of its allies and enemies combined.

And yet America too often seems hopeless and helpless. President Barack Obama is a churchgoing man and must know the story in St. Matthew’s Gospel of the Centurion, “having soldiers under me,” who speaks of the kind of temporal authority he can exercise. “I say to this man, Go, and he goeth; and to another, Come, and he cometh; and to my servant, Do this, and he doeth it.”

Today, when the American president says “Go,” no one goeth. That includes even his supposed friends. The Middle East countries that have received enormously the largest sums in American aid are Israel and Egypt. But what happens when the White House tries to call in part of the debt?

First Obama begged Benjamin Netanyahu to desist from building any further settlements for a short period, to encourage a renewed peace process and help the Palestinian leadership. Then the president implored Mubarak to leave right away and enable an orderly transition of power. Both men studiously ignored him. Never mind those billions after billions of dollars their countries have accepted. In their dealings with the Americans, Bibi and Hosni alike might have borrowed the sarcastic words of Prince Schwarzenberg of Austria after the Russians had helped suppress the Hungarian rising in 1849: “They will be astonished by our ingratitude.”

For that matter, in different contexts, no amount of American cajolery or veiled threats can persuade the Chinese government to revalue their currency, nor induce the Pakistani government to cut links between its intelligence services and the Taleban.

From one side of the world to the other, countries are doing what they think best for themselves, rather than what the White House, the State Department or the Pentagon think they should do.

Some of the reasons for this helplessness are obvious enough. President Obama has been criticised for excessive caution in handling the Egyptian crisis, advising Mubarak to stand down but not putting severe pressure on him, expressing approval of the democracy movement without fully embracing it. He showed something of the same nervous hesitation earlier over popular protest in Iran. His critics say that this nervosity is ignoble and misplaced, and that fears about a new revolt sweeping the Middle East are exaggerated. Maybe so, although there are well-informed people, among them an Oxford historian and a former American diplomat, who pour cold water on the enthusiasts.

In his learned recent book The Arabs, Eugene Rogan gave his view that Islamists would likely win free elections in most Arab countries today. And another illuminating book, The Much Too Promised Land, by Aaron David Miller, tells of his years as a State Department official engaged in what is forlornly called the peace process. As he says, in the Middle East today the United States finds itself “trapped in a region which it cannot fix and it cannot abandon,” where America is “not liked, not feared, and not respected.”

Although Israel is not liked either, it’s feared — but also fearful. The Israeli reaction to events in Egypt has been close to panic-stricken. David Horovitz, editor of the Jerusalem Post, thinks that Israel’s “strategic assumptions were liquefied almost overnight” by the “colossal psychological blow” from Cairo. “The Israeli government is freaking out,” says Shmuel Bachar of the Israel Institute for Policy and Strategy. Those apprehensions may also be exaggerated, but they certainly aren’t incomprehensible, and it could be that the most intransigent Israelis are more clear-sighted than starry-eyed Americans who urge Israel to embrace the Arab popular rising.

As Bachar says: “For the past 30 years we have depended on Egypt’s peace treaty with Israel. Now, suddenly, we have rediscovered the existence of something called an Egyptian public, the existence of which we’ve vigorously tried to ignore.”

We still don’t know for certain the degree of popularity enjoyed by Islamists, in Egypt or elsewhere. Only putting it to the electoral test can answer that, and Rogan might prove to be too bleak in that assessment, although the election of a Hamas government in Gaza gives some weight to it. But he is surely right to say “the inconvenient truth about the world today is that, in any free election, those parties most hostile to the United States are likely to win.” This is a strange new world the Americans find themselves in, and one where they are finding it harder than ever to impose their will on anyone anywhere.

Geoffrey Wheatcroft is the author of “The Controversy of Zion,” “The Strange Death of Tory England” and “Yo, Blair!”