Israeli Defense Minister Moshe "Bogie" Ya'alon is no one's idea of a leftist. Ya'alon opposed Israel's 2005 disengagement from Gaza and is openly skeptical of a two-state solution. He's referred to the threat from Palestinian militants as a "cancer" that has "to be severed," and bashed Secretary of State John Kerry for his "obsessive" and "messianic" commitment to the peace process.

Yet, Friday morning, Ya'alon resigned in protest, blasting Prime Minister Benjamin Netanyahu and his Likud Party for drifting too far to the intolerant right.

"The State of Israel is patient and tolerant toward the weak among it and minorities," Ya'alon said in his resignation speech. "But to my great regret, extremist and dangerous elements have overrun Israel as well as the Likud Party, shaking up our home and threatening harm to those in it."

Now, the timing is certainly political: Netanyahu had just given Ya'alon's job away in a bid to secure his own political positioning. But Ya'alon's resignation speech is also sincere: In the past 15 years, Israel has drifted extremely far to the right — to the point where, even for many staunch Zionists, the country's politics are no longer recognizable.

Ya'alon is partly a casualty of political maneuvering

In Israel's fractured political system, no one party holds a majority of seats in the Knesset (Israel's Parliament). Generally, the party that wins the most votes in the election forms a coalition government, where they get smaller parties to join with them and thus control a majority of seats in the Parliament as partners.

Since last March's elections, Netanyahu's coalition has been very precarious. Likud only had enough coalition partners to control 61 out of 120 seats in the Knesset, meaning that passing legislation required literally everyone in the coalition to get on board. If even the smallest party in the coalition left, his government wouldn't have a majority anymore.

This is clearly a dangerous position for Netanyahu, and this week he settled on a plan to fix it. He invited Yisrael Beiteinu, a right-wing nationalist party, to join the coalition. That would give the coalition control of 67 seats, a far more comfortable governing margin. In return for joining Netanyahu's government, Yisrael Beiteinu leader Avigdor Lieberman would take Ya'alon's position as defense minister.

That left Ya'alon out of a position in Cabinet. Rather than try to stay in the government or Knesset, he chose to resign his Parliament seat altogether.

Israel's government is really, really right-wing

Ya'alon didn't have to quit the party — the rumor in Israel is that Netanyahu wanted him to stay on as foreign minister. But he chose to do so, and to deliver a sharply worded speech condemning Israel's new government to boot. Clearly, Ya'alon had an ideological axe to grind.

To understand why, you need to understand a little more about the ideological divides inside Israel.

Historically, the left-right split in Israel has focused on security issues: The left favors concessions to the Palestinians and a more dovish foreign policy, while the right is less sanguine about a two-state solution and more militaristic.

However, there's also a divide inside Israel on issues about tolerance and individual rights. Certain hard-right factions inside Israel have recently pushed bills cracking down on non-governmental organizations that do things like calling for Israeli soldiers to be prosecuted in international courts or calling for boycotts, divestment, and sanctions (BDS) of Israel. They've also pushed bills declaring Israel a "national state of the Jewish people" (and not, by implication, its Muslim or Christian citizens).

It's possible to be both a security hawk and a relative liberal on issues of rights. Israeli President Reuven Rivlin, for example, has historically been skeptical of a two-state solution and a prominent voice in favor of tolerance and equality when it comes to Arab citizens of Israel. Ya'alon fits the same profile.

However, Likud is going through a process that some observers have referred to as Tea Party-ization. Younger Israelis tend to be more conservative, increasingly empowering factions inside the party that are more hostile both to the peace process and civil libertarian concerns. That causes center-right voters to defect to centrist parties, pushing the party ever rightward as it seeks to play to its increasingly conservative support base.

People with Ya'alon's views, then, have becoming more marginalized over time. He's quitting, as he openly said in his speech, because these harder-right factions have become ascendant both in Likud and Netanyahu's government in general.

He has real reasons to worry about Netanyahu's government. Incoming Defense Minister Lieberman previously pushed for a bill that would force Israelis (including Arabs) to swear loyalty oaths to the government before they could vote. He also floated a plan to strip some Arab citizens of Israel of their citizenship and transfer them to a future Palestinian state.

Forty-six percent of Israelis support a law that would ban public criticism of the government

Justice Minister Ayelet Shaked, from the religious nationalist Jewish Home Party, has been pushing for over a year now to pass laws imposing special restrictions on foreign-funded NGOs. In practice, this would disproportionately impact left-wing, anti-occupation groups, labeling them as foreign agents.

Just several months ago, an Israeli soldier executed a Palestinian attacker who was already disarmed and lying on the ground. Ya'alon, who was the Israeli Defense Forces chief of staff before going into politics, condemned it, calling the killing "very grave and absolutely contrary to the values of the IDF and its battle ethics." Netanyahu initially backed him, but softened his condemnation under pressure from the political right. Netanyahu even called the soldier's father to reassure him that his son would be well-treated.

The positions of Israel's leadership reflect broader anti-democratic and anti-Arab trends in Israeli society. Polling by the Israeli Democracy Institute finds that a growing number of Israelis — a plurality, now — believe Israel should privilege its Jewish identity over its democratic one. IDI also found that 46 percent of Israelis support a law that would ban public criticism of the government.

Both the behavior of Israel's government and opinion trends among its population imperil the country's status as a tolerant democracy. That's something that people like Ya'alon, who prize both the country's Jewish and democratic identities, can't tolerate. Hence why he resigned.

"To my great regret, I have recently found myself in difficult disputes over matters of principle and professionalism with the prime minister, a number of cabinet members, and some lawmakers," Ya'alon said.

Israel's new opposition?

Though Ya'alon left the Knesset, he committed to returning to public life at some point. "In the future I will return to contend for Israel's national leadership," he said.

This has led some Israelis to speculate that Ya'alon will return to take on Netanyahu's government. "In one short speech, Moshe Ya'alon has just positioned himself as the new leader of the Israeli opposition," Anshel Pfeffer, a columnist at the left-wing newspaper Ha'aretz, tweeted.

Twenty years ago, the idea that someone as hawkish as Ya'alon would lead the opposition against a Likud government would have sounded ridiculous. But since the collapse of the peace process and the Second Intifada in the early 2000s, the traditional Israeli peace camp has collapsed, as Israelis became increasingly skeptical of a two-state solution. The Labor Party, long the stalwart of the left, moved to the center.

"I wouldn't call Labor that traditional Jewish political left anymore … It is the center, and it's moved in many ways closer to the right, particularly on the peace process," Brent Sasley, a professor at UT Arlington who studies Israeli politics, told me last year.

During the 2015 election, Labor leader Isaac Herzog played down his support for a negotiated settlement with the Palestinians, recognizing (correctly) that the peace process was one of the right's stronger issues. He even entered negotiations to join Netanyahu's government earlier this week, before Lieberman's entrance was announced.

The point, then, is that there's a leadership vacuum to Netanyahu's left. And while Ya'alon is no leftist, he has just anointed himself one of Israel's most prominent critics of the country's rightward drift.