President Trump announced a deal with Morocco on Thursday that included two major provisions: Morocco will establish diplomatic relations with Israel, and the U.S. will recognize Morocco's sovereignty over the disputed territory of Western Sahara.

Why it matters: The U.S. is now the only Western country to recognize Moroccan sovereignty over Western Sahara, reversing decades of U.S. policy. With six weeks left in his term, Trump provided Morocco a diplomatic breakthrough for which it has lobbied for decades.

Behind the scenes: The deal was reached through bilateral U.S.-Morocco negotiations, with Israel in the loop but not involved in the talks, Axios' Barak Ravid reports.

Background: Western Sahara, a sparsely populated territory on the northwest corner of Africa, is sometimes referred to as "Africa's last colony." It was annexed by Morocco in 1975 after former colonial power Spain surrendered control.

• The local Sahrawi population, represented by the Polisario Front, fought Morocco for independence until the UN brokered a peace agreement in 1991. That agreement called for an independence referendum, which has never been held.
• Morocco, which administers two-thirds of the territory, has continued to strengthen its position in Western Sahara, but without recognition from the international community — until now.
• “In the small world of diplomacy, it's a bomb. Forty years of debate erased in one tweet," tweeted Gérard Araud, the former French ambassador to the UN and U.S. "What will the Biden administration do?”

What to watch: Biden may do nothing, recognizing that reversing Trump's decision would damage America's relationship with Morocco and likely derail the kingdom's normalization process with Israel.

• “I would be surprised if they undo it," says Intissar Fakir, a North Africa expert at the Carnegie Endowment. "Trying to turn back the clock on this could cause more of a headache than just going with it and being as ambiguous about it as they can be."

The other side: Normalization with Israel would, on its own, be "a very risky move for Morocco," Fakir says.

• Just 4% of Moroccans polled in the 2019–2020 Arab Opinion Index supported diplomatic recognition for Israel, with 88% opposed.
• The kingdom has taken a cautious approach to Thursday's announcement, at least for domestic audiences, but is unlikely to see the sort of public anger that normalization with Israel would otherwise generate.

“The Western Sahara cause is a very unifying cause in Morocco. The vast majority of Moroccans really do stand behind the monarchy in that regard," Fakir says.

• The monarchy's top foreign policy objective has for years been to secure as much recognition as possible for its control of the territory, she says.
• "Having such an important win really bolsters their legitimacy, particularly at a time when the country is going through a lot of challenges."
• In Algeria — where the Polisario is based and where some 200,000 Sahrawis live, many of them in refugee camps — the reception will be far less positive.

Driving the news: The announcement also comes just a month after the ceasefire between Morocco and the Polisario Front collapsed following nearly three decades.

• The skirmishes began after Morocco violently cleared a highway that had been blockaded by Sahrawi protesters.
• The Polisario Front then announced a return to armed resistance, though there have been no reports of significant victories or casualties to date.

Where things stand: "There's an entire generation of Sahrawi's who have been essentially waiting on some kind of movement on this issue," Fakir says.

• With the diplomatic momentum heading in the wrong direction, "there's not a whole lot the Polisario can do other than to go back to conflict to try to bring some sort of attention to this issue," Fakir says.

The bottom line: Morocco has never been in a stronger position in the conflict, particularly after Trump's announcement.