Israel captured the West Bank over five decades ago, during the 1967 Six-Day War. Yet talk of West Bank annexation has only recently entered the Israeli political mainstream, with attendant concern overseas. This naturally invites the questions: why now, and why does it matter?

Annexation means the formal absorption of the West Bank by Israel in part or in whole. Nearly 52 years after the Six-Day War, the idea is that the West Bank is under a temporary occupation, yet its status actually does differ from Israel within its pre-1967 borders (what is often referred to as “sovereign Israel” or “Israel proper”).

As it stands, the West Bank is held by Israel in a state of belligerent occupation. This designation does not necessarily prejudge the exact parameters of a future political agreement, but it does mean that under international law, Israel, as the occupying power, has certain humanitarian obligations to the population of the occupied territory.

Supreme governing authority in the West Bank technically runs through the Israel Defense Forces. This means the Knesset does not legislate for the West Bank, but that the local IDF commander applies the law to Jewish settlers, who are Israeli citizens, while the territory itself and its non-Israeli (Palestinian) residents are subject to the military’s jurisdiction (although, notably, the Israeli military operates under civilian political control). In the context of a future peace agreement, there are fewer complications to ceding territory that is under a temporary administration than land with the same legal standing as the rest of the state, along the lines of Tel Aviv or West Jerusalem.

By applying Israeli sovereignty and civilian law to the West Bank, the Knesset would be able to directly govern the West Bank, bypassing the military. Most pro-annexation Israeli officials discuss applying Israeli sovereignty to Area C (60 percent of the West Bank) without citizenship for the 2.3 million Palestinians living in the non-contiguous Areas A and B. This means millions of Palestinians would live on the sovereign territory of a country in which they lack voting rights.

The truth is, the day after annexation would probably not look much different than the day before for the Palestinians and Israelis in the West Bank. It will not come in one fell swoop and the day-to-day functions of Israeli control will likely look the same, at least in the immediate aftermath. While many annexationists discuss extending formal Israeli control to all of the West Bank or all of Area C (60 percent of the West Bank), it is far more likely that several large settlements (such as Ma’ale Adumim or the Etzion bloc) will be annexed piecemeal rather than one sudden land grab.

A lot of the consequences of annexation hinge on the diplomatic reaction. The unilateral acquisition of territory is generally frowned upon in international politics. Section II of the UN Charter calls on states to settle territorial disputes peacefully, and relevant Security Council resolutions reinforce this principle. In practice, however, some annexations have gone without tangible fallout (the Jordanian annexation of the West Bank and Israeli annexations of East Jerusalem and the Golan Heights, for instance, elicited mostly verbal condemnation) while others have prompted sanctions (like Russia’s annexation of the Crimea from Ukraine). Israeli annexation of the West Bank is liable to generate backlash as it upends the internationally accepted model of two states for two peoples, with Israel formally incorporating territory widely viewed as part of a future Palestinian state. The question is when Israeli actions become a bridge (or settlement) too far for other countries and for the Palestinian Authority (the transitional quasi-state entity governing parts of the West Bank). What exactly would cause the PA to collapse? How long could Israel’s peace treaties with Egypt and Jordan survive? Would the European Union impose sanctions? What about the next American administration? It is difficult to forecast any of these eventualities precisely, though Commanders for Israel’s Security have done a good job of estimating the costs of the fallout.

Israel has avoided these consequences because up until now even right-wing governments refrained from dramatic steps in the direction of annexation. Prime Minister Netanyahu has allowed moves like the Regulation Law (retroactively legalizing far-flug settlement outposts), as well as legislation terminating the Israeli High Court of Justice’s role as the court of first instance for West Bank Palestinian petitions (superficially normalizing the West Bank’s status in relation to Israel without improving Palestinian rights there). These incremental processes are known as creeping annexation. Yet more public moves directed at major settlement blocs have not occurred.

In the past two years, the pro-annexation camp in Israel has brought its agenda more into the open. In December 2017, the Likud Central Committee (in a near-unanimous vote) endorsed annexing West Bank settlements (without stipulating the precise extent of this land grab). This was largely the result of lobbying from the Sovereignty Movement, a NGO pushing for annexation. Moreover, the policies of the Trump administration foster a more permissive environment for Israel’s annexationists. Beginning with the relocation of the American Embassy from Tel Aviv to Jerusalem, the White House has provided a series of perceived political gifts to Israel without asking anything in return. Most recently, American recognition of Israeli sovereignty over the Golan Heights (captured from Syria in 1967 and annexed in 1981) has been interpreted as a green light by some annexationists for a more aggressive approach to the West Bank. There are now serious questions as to whether the Trump administration’s Israeli-Palestinian peace plan (if it is even released) will adhere to the traditional model of two states for two peoples. If it does not, the United States could end up providing Israel valuable diplomatic cover for the formal integration of significant parts of the West Bank.