Israel's election: The most important things to know

Israelis are going to the polls on Tuesday for a second general election in just five months. What happens matters not only in Israel but also beyond.

Here are five of the most important things to know.

Israel has the strongest military in the Middle East (and is widely believed to have a nuclear arsenal), and the prime minister decides when to send it into action.

Although the country is not fighting any full-scale wars at the moment, there is the ever-present danger that fresh conflict will erupt with its regional foes.

The two main contenders for the premiership have both positioned themselves as tough on security - the incumbent, Benjamin Netanyahu, has followed a strategy of air strikes and covert action against threats from neighbouring countries, while his most prominent challenger, Benny Gantz, is a former military chief on whose watch many such operations were carried out.

Whoever wins will have to decide how to deal with the biggest dangers - the growing presence on Israel's borders of forces backed by Iran, Israel's arch-enemy, and a belief that Iran wants to develop a nuclear bomb - and whether to risk a war whose consequences, observers have warned, will be catastrophic.

The fate of the Palestinians depends on who is in power in Israel, since Israel occupies land which they seek for a state of their own.

Mr Netanyahu says he will never agree to a sovereign Palestinian state with powers like any other country (something which he says will be a serious threat to Israel).

He has also pledged to annex Jewish settlements in the West Bank, and a swathe of land known as the Jordan Valley (which comprises about 30% of the West Bank). Because they are built on occupied territory, the settlements are considered illegal under international law, though Israel disputes this.

The Palestinians, who want the settlements removed, say such a move would make a Palestinian state impossible and kill the peace process once and for all.

It is less clear where Benny Gantz stands on the issue. He has not said whether or not he accepts the idea of a Palestinian state, although, like Mr Netanyahu, he rejects withdrawing from all of the occupied West Bank and has also said he will not divide Jerusalem, whose eastern part Palestinians want to be the capital of a future state.

While Mr Netanyahu is politically right wing and ideologically driven by Jewish claims to the land based on the Bible, Mr Gantz is considered more centrist and moderate.

This may sound paradoxical but Israel's political system - a form of proportional representation - means it is as much about political bargaining after an election than it is to do with the poll itself.

Israel has always been governed by coalitions of right-wing or left-wing blocs (or occasionally governments of national unity) - so the outcome of an election depends on what smaller parties demand from the winner (such as ministerial positions or budget pledges) in return for their support.

Sometimes even a candidate whose party wins the most votes on the night does not become the prime minister if they cannot form a majority coalition comprising at least 61 seats in parliament.

They have several weeks to try to do this after the election - and if they cannot manage it, the president can nominate another candidate for prime minister (in 2009, Mr Netanyahu's Likud party came second but he ended up re-appointed as PM). In April's election, Mr Netanyahu won the most votes but failed to form a coalition, which is he why he called a snap poll for 17 September.

Polls show that the cost of living is more of a priority to Israelis than solving the Israeli-Palestinian conflict. Security is also high on their agenda.

Perhaps surprisingly to outsiders, corruption allegations against Prime Minister Netanyahu, who could be charged in the near future, are not particularly bothering voters, especially anyone right of centre.

However, the fear (notably among left-wing voters) that Israeli democracy is under threat has grown amid concerns over expectations that Mr Netanyahu will seek coalition agreement about legislation providing immunity from prosecution while he is in office and planned reforms that would allow governments to overrule Supreme Court rulings (seen by critics as another way to keep Mr Netanyahu safe).

One major issue which cuts across right-left political boundaries is that of conscripting more ultra-Orthodox Jews - who are currently exempted from the draft - into the military.

Failure to agree on this was among factors that led to the collapse of Mr Netanyahu's coalition in December 2018, triggering April's election. The same issue also brought an end to the negotiations to form a new coalition, precipitating this poll.

Aside from Mr Netanyahu and Mr Gantz, there are two other key figures who could make a big difference to what happens next.

Avigdor Lieberman - An ally-turned-rival of the prime minister, Mr Lieberman leads the right-wing secular Yisrael Beiteinu (Israel Our Home) party.

His withdrawal from Mr Netanyahu's coalition in November 2018 (he considered the PM too weak in dealing with militants in Gaza) left the prime minister with a majority of one. The following month, the coalition collapsed. If his party performs as well as polls predict, Mr Lieberman could hold the balance of power.

However, he has said the only way he will help return Mr Netanyahu to office is if he agrees to a government of national unity and shares power with Benny Gantz's Blue and White party - something the prime minister has ruled out.

Ayelet Shaked - Mr Netanyahu's former justice minister is the leader of the religious nationalist Yamina (Rightwards) alliance. The grouping's performance will be crucial to Mr Netanyahu's ability to put together a governing coalition.

Although Ms Shaked is also a rival of Mr Netanyahu, she has said she will support him in forming a right-wing government. Whether this will be sufficient to remove Yisrael Beiteinu's ability to make or break a Netanyahu-led coalition remains to be seen.

Politically hard-right, Ayelet Shaked advocates annexing those parts of the occupied West Bank placed under interim Israeli control in past peace deals with the Palestinians, and says that if Mr Netanyahu forms the next ruling coalition, she will make sure he follows through on his pledge to do it.