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The U.N. has accepted a request by observer state Palestine to join the International Criminal Court, clearing the way for possible war crimes complaints against Israel. Palestinians hope the tribunal will give them more leverage in a lopsided conflict and keep a distracted world focused on their statehood claims.

But prosecution of Israel is not assured, and cases before the world's war crimes tribunal can take years. Meanwhile, Israel is gearing up for a counter offensive that could land senior Palestinians in the defendants' dock. Here is a look at the looming showdown at The Hague.

WHAT HAPPENS NOW?

Palestine formally joins the court April 1 as its 123rd member, U.N. Secretary-General Ban Ki-moon said in accepting Palestinian President Mahmoud Abbas' ratification of the court's founding statute. Palestine was recognized by the U.N. General Assembly in 2012 as a state, covering the West Bank, Gaza Strip and east Jerusalem, lands Israel captured in 1967. Palestine exists in theory only, with Israel in full control of most of the occupied territory, but will be treated as a state at the ICC. Israel is not a member of the court and has no plans to join, but its actions in the Palestinian territories can now be investigated and prosecuted by the court.

WHAT CASES WILL THE PALESTINIANS SUBMIT?

They will focus on last year's 50-day war between Israel and the Islamic militant Hamas group in Gaza and on Israeli settlement construction on occupied lands. More than 550,000 Israelis live in settlements built since 1967 in the West Bank and east Jerusalem. The court's 2002 founding charter says a state commits a war crime if it transfers its civilians to territory it occupies.

Abbas' adviser Saeb Erekat said Wednesday that "we want to go forward" on both cases.

WHAT'S NEXT ON THE GAZA WAR COMPLAINT?

This week, Palestine accepted the court's jurisdiction over its territory, going back to June 13, 2014. That's the day after three Israeli teens were abducted and killed by Hamas militants in the West Bank, an attack that set off events culminating in the Gaza war the following month.

In the war, Israel launched some 5,000 airstrikes on Gaza, while Gaza militants fired thousands of rockets at Israel. More than 2,200 Palestinians were killed, most civilians, according to the U.N., while 72 people were killed on the Israeli side, including 66 soldiers.

Palestinian human rights groups are already collecting evidence against Israel, including thousands of witness statements. The strongest potential cases, including airstrikes on homes killing multiple family members, are being prepared for the ICC, said rights activist Shahwan Jabarin.

DO PALESTINIANS FACE POSSIBLE WAR CRIMES INVESTIGATIONS?

Yes. U.N. investigators say Hamas has committed war crimes by indiscriminately firing rockets and mortar rounds at Israeli civilians and launching attacks from civilian areas in Gaza. The militants, who seized Gaza from Abbas in 2007, have carried out such attacks for more than a decade and Israel says it launched the last Gaza war to stop rockets.

The militant group claims it is engaged in legitimate resistance to occupation and has supported Abbas' request for ICC membership.

Israel says Abbas and his aides could also face prosecution, arguing he is legally responsible for Hamas' actions because the group supports his Palestinian unity government.

Separately, an Israeli group, Shurat Hadin, filed war crimes complaints against Abbas, three other Palestinian officials and Hamas leader Khaled Mashaal. The group says it is preparing 30 more complaints that it hopes will deter Palestinians from seeking ICC action against Israel.

WHAT IS ISRAEL'S POSITION?

Foreign Ministry spokesman Emmanuel Nahshon alleges the Palestinians chose "legal warfare" over peace negotiations. Intermittent negotiations over 20 years have failed, most recently last year.

Israel retaliated for the Palestinian move to join the ICC by freezing the transfer of more than $100 million a month in taxes it collects for the Palestinians. The suspension means Abbas cannot pay salaries of 153,000 employees, dealing a major blow to a shaky economy. Israel has threatened further sanctions.

WHAT IS ISRAEL'S DEFENSE?

Israel denies it committed war crimes in Gaza, insisting it did its utmost to spare civilians. At the same time, Israel says its military is conducting a credible investigation of alleged violations of rules of combat, with 13 criminal probes launched and dozens of incidents under review. This could buy Israel time. The ICC is a court of last resort and will only step in if it believes war crimes allegations aren't investigated properly at the state level.

Concerning settlements, Israel says they are not illegal. It portrays the West Bank as disputed rather than occupied and says east Jerusalem is part of Israel's sovereign territory following its 1967 annexation — though the annexation was not recognized internationally.

IS AN ICC INVESTIGATION ASSURED?

No. It is up to ICC prosecutor Fatou Bensouda to decide whether to open an investigation. She wrote in August that her approach to Palestine "will be no different" from that to other states if the court receives jurisdiction.

Stepping into the Israeli-Palestinian conflict could broaden the reach of the court, which so far only prosecuted African dictators and warlords. But it's also a huge challenge, considering setbacks suffered by the court, including the recent collapse of the prosecution of Kenya's president.

HOW LONG COULD IT TAKE?

Cases can take years, from an initial review to launching an investigation and possibly filing charges, said Alex Whiting, a senior official in the ICC prosecutor's office from 2010-2013 and now a Harvard law professor.

War crimes allegedly committed during combat are among the most difficult to prove, said Whiting, suggesting a Gaza war complaint would face stiff challenges.

WHAT DO THE PALESTINIANS WANT?

Joining the court is part of a broader strategy to involve the international community in the conflict with Israel, after Palestinians lost faith in bilateral talks and in the United States as a broker.

Some say that simply joining the court is an achievement for the Palestinians because it reframes the conflict with Israel as an issue of justice and war crimes.

WHAT ARE THE RISKS?

In joining the ICC, the Palestinians are transforming their relations with Israel from tense to hostile, reducing chances of negotiations on statehood.

The Palestinian Authority, Abbas' self-rule government, could collapse if Israel continues to freeze tax transfers and Congress cuts off funding, as threatened. This could cost Abbas his job, damage ties with the U.S. and move Palestinian independence further out of reach.