Palestinian President Mahmoud Abbas, center, speaks during a meeting with the Palestinian Central Council, a top decision-making body, at his headquarters in the West Bank city of Ramallah last April. (Majdi Mohammed/AP)

The Palestinian Authority officially became a member state of the International Criminal Court at The Hague on Wednesday, opening an unprecedented new front in its self-declared “diplomatic war” against Israel.

Whether Israelis will ever be prosecuted for war crimes in the court is uncertain. But the move to join the international body has angered Israeli Prime Minister Benjamin Netanyahu, who vowed that no Israeli military commander “will ever be dragged” before the tribunal.

Yet the Palestinians have gotten further in their bid than most would have predicted a year ago.

In a move once described by the Palestinians as “the nuclear option,” they have successfully joined the court, which many Israeli legal experts said would never happen. The tribunal’s top prosecutor has launched a preliminary examination to determine whether grave crimes were committed in the Israeli-occupied territories and if the ICC has proper jurisdiction to investigate.

U.S. diplomats had warned the Palestinians not to join the court, arguing that the move would only further undermine already fractious relations with Israel, anger a Republican-controlled Congress that provides $400 million in annual aid and dim prospects for negotiations to create a sovereign Palestinian nation.

Palestinian leaders, however, celebrated on Wednesday, saying their accession to the court will serve to protect Palestinians in the future and to expose Israel to possible prosecution for past alleged war crimes in the Gaza Strip and the West Bank.

Palestinian officials imagined a day when Israeli generals and senior officials might find themselves summoned to appear before the tribunal or be arrested on ICC warrants as they pass through countries that are members of the court.

“For us this is a very, very important step,” said Mustafa Barghouti, a top leader of the Palestine Liberation Organization. “Now every Israeli soldier, every general will have to consider the court.”

He said: “It changes everything. It changes the balance of power.”

The Palestinians allege that Israel committed war crimes during the summer offensive in the Gaza Strip, which left more than 2,100 Palestinians dead, many of them civilians.

They also charge that the ongoing construction of Israeli settlements and demolition of Palestinian homes in the West Bank is a war crime, as it facilitates a transfer of populations into occupied territory.

Israel disputes this, and Israeli legal experts counter that the Palestinian accession to the court means little.

“It is a useless public relations exercise,” said Alan Baker, former legal adviser and deputy director-general of the Israeli Foreign Ministry.

Israel and the State Department have argued that the Palestinians should not be granted membership to the court because “Palestine” is not a true state.

The Palestinians tried to join the court in 2009 but were denied admission. But after the United Nations awarded them “non-member observer state” status in 2012, the Palestinians’ application to become party to the Rome Statute and accede to the court was accepted this year.

By joining the ICC, the Palestinians are also exposed to scrutiny. Israel has charged that the militant Islamist movement Hamas and its militia are guilty of war crimes for the indiscriminate rocket fire at civilian population centers in Israel. Amnesty International concluded the same thing in a report last week.

The human rights group has argued that both Israel and Hamas committed crimes in the last Gaza war and that international tribunals and threats of war crime charges may serve to restrain both sides in future conflicts.

After the collapse of the last round of U.S.-led peace talks last year, the Palestinians have launched a vigorous, focused campaign to “internationalize” their conflict with Israel through the ICC, the United Nations and its agencies, and by seeking resolutions and affirmations of statehood by foreign governments, especially in Europe.

“If the Israelis say the court means nothing to them, why are they the ones who are panicking?” Barghouti asked.

After the Palestinians submitted their paperwork to join the ICC in January, Netanyahu ordered his government to withhold the transfer of $375 million in quarterly customs taxes that Israel collects on behalf of the Palestinian Authority, which uses the money to pay salaries, including wages for police.

On the advice of his security team, which was fearful about a breakdown in law and order in the West Bank, Netanyahu reversed himself and announced Friday that Israel will begin transferring the funds again.

Saeb Erekat, former chief peace negotiator for the Palestinians, called joining the court “historic.”

Earlier, Erekat complained that the Palestinians were damned by Israel and the United States no matter what.

“I’m telling Palestinians, ‘Don’t use violence.’ We’re going to use the civilized means of international law to achieve our goals, our independence, our freedom,” ­Erekat recently told NPR.

“Then people threaten me that if I go to court, they’re going to suspend my aid and so on,” he said. “No! I am the victim. They should go to those who commit the crimes and tell them to stop committing crimes, and then we don’t have to go to courts.”

The United States, China, Russia and other world powers are not members of the ICC, but 123 countries are, including 28 members of the European Union.

The ICC’s top prosecutor, Fatou Bensouda, began a preliminary examination “into the situation in Palestine” on Jan. 16 to consider issues of jurisdiction, admissibility and the interests of justice.

The ICC was established in 2003. Preliminary examinations by the prosecutor’s office have lasted for months and in some cases for 10 years — and counting.

Palestinian officials have stressed that the ICC will not end the almost 50-year Israeli military occupation or lead to a state. The ICC prosecutes individuals, not nations.

If the ICC prosecutor concludes that the facts lead her to open a formal investigation, a pretrial chamber of ICC judges will rule on whether to go forward. A trial may then follow.

ICC prosecutors have examined allegations of war crimes in 20 countries but opened investigations in only eight. The court has concluded three trials, winning two convictions.

Eugene Kontorovich, a professor at the Northwestern University School of Law, said that it is possible that the ICC judges will ultimately decide that the Palestinians do not have standing at the court or that the Israelis should not be subject to an investigation, for example, because they carry out their own inquires.

Kontorovich said that the court has operated for only a dozen years and that there has not been enough case law to predict what may happen next.