JERUSALEM — When Israel declared its independence in 1948, President Harry Truman rushed to recognize it. He took just 11 minutes, and Israelis, about to go to war to defend their infant state, were euphoric.

Seventy years to the day — and nearly as long since Israel declared the holy city of Jerusalem its “eternal capital” — the United States will formally open its embassy on a hilltop here two miles south of the Western Wall.

The embassy’s move from Tel Aviv and President Trump’s recognition of Jerusalem as Israel’s capital — reversing decades of American foreign policy — comes at a moment so fraught with both pride and peril that Israelis seem not to know what to feel.

Israelis find it hard to rejoice when they find themselves doing some of the same things they did back in 1948: listening for civil-defense sirens, readying bomb shelters and calling in reinforcements to confront threats to the north, south and east.