Do Trump and Netanyahu see eye to eye?
If nothing else the visit by the Israeli Prime Minister Benjamin Netanyahu should help to clarify President Trump's Israel/Palestine policy and, perhaps, cast further light on who will be running it.
Mr Trump's starkly pro-Israel campaign rhetoric appeared to upend bedrock US positions on Middle East peace. His chaotic transition has only added to the confusion.
So far it's been like Kremlinology, says Michael Koplow of the Israel Policy Forum, an American-Jewish Organization that advocates for a two-state solution to the conflict.
He's referring to the Soviet-era practice of reading between the lines of official photographs, trying to figure out "who's on top, who's on the bottom, whether career officials worked on this or were frozen out. There's no direct chain of command so far as I can tell."
The competing cast of characters is led by Donald Trump's son-in-law Jared Kushner, an orthodox Jew with personal and religious ties to Israel who has not spoken publicly about his political views.
Mr Trump has also included among his advisers ideologically driven, pro-Israel figures who reject the notion of a Palestinian state and support the building of Jewish settlements on Israeli-occupied land expected to form part of that state.
His cabinet posts, on the other hand, hold more traditional views. Defence Secretary James Mattis is on record warning about the dangers to Palestinian statehood posed by continued settlement building.
"Either (Israel) ceases to be a Jewish state or you say the Arabs don't get to vote - apartheid," he said at a security forum in 2013.
And new the US secretary of state, former ExxonMobil chief executive Rex Tillerson, endorsed the two-state solution during his confirmation hearing.
The picture is complicated by continued staffing vacancies in second- and third-tier positions at the State Department and the National Security Council, which together run the nuts and bolts of Middle East policy.
The lack of direction at that level contributed to disjointed US responses on recent Israeli announcements of a settlement construction spree.
After initial radio silence from the White House, an administration official speaking to the Jerusalem Post newspaper denounced the plans as "unilateral" moves that would "undermine" peace efforts - language from a State Department draft based on long-standing US policy.
The next day the White House issued a formal statement that was gentler in tone.
"While we don't believe the existence of settlements is an impediment to peace," it said, "the construction of new settlements or the expansion of existing settlements beyond their current borders may not be helpful in achieving that goal… the Trump administration has not taken an official position on settlement activity".
That ambiguity has frustrated some US officials.
Even during the transition between Republican Secretary of State Condoleezza Rice and Democrat Hillary Clinton, "we still produced things that said settlements are bad, that we believe in two states living side by side", said one. "We can't even say that anymore, nothing is for sure."
Ghaith al Omari, an adviser to the Palestinian negotiating team during the transition from Bill Clinton to George W Bush, counters that "upheavals are normal" in transitions, noting that high-level contacts between the Clinton administration and the Palestinians nearly vanished in the first months under Mr Bush as he formulated his policy, similar to the situation now.
This is uncomfortable for the Palestinians, he said, but "not yet a crisis", although he admitted the best they could hope for was "do no harm".
Palestinian Authority (PA) officials are extremely uncomfortable about the lack of contact, especially President Mahmoud Abbas, who famously claimed to be the first world leader President Barack Obama called when he took office.
So far this White House hasn't responded to Mr Abbas' attempts at contact, although Israel's Haaretz newspaper reported that the PA intelligence chief did meet some of Trump's advisers last week.
The key question is which parties will have the most influence in Middle East decision-making.
Secretary of State Rex Tillerson has no experience in diplomacy or government and has yet to name a deputy, a post that will be crucial in determining how much weight his department wields on this issue.
Meanwhile, Mr Trump has empowered two of his Jewish lawyers, Jason Greenblatt and David Friedman, both of whom have extreme right-wing nationalist views. He's named Mr Greenblatt his special representative for international negotiations, and nominated Mr Friedman as ambassador to Israel.
That doesn't mean he necessarily shares their views.
"The two lawyers closest to him happened to be religious, orthodox and right-wing on Israel. That's the coincidence," says Mr Koplow.
"But because that's who surrounds him the views that come through are very right-wing on Israel."
Mr Trump's chief White House strategist, Steve Bannon, brings in yet another dimension.
He's the former head of Breitbart News, which he has described as a platform for the alternative right, a broad movement that encompasses both extreme conservatives and white supremacists.
The website supports a hard-right nationalist position on Israel. But it has also been accused of attacking American Jews it deems not sufficiently pro-Israel.
It is not clear how close Mr Bannon will be to Israeli/Palestinian policy making. But a White House statement on the Holocaust that failed to mention Jews rang alarm bells, and prompted a rare riposte on Twitter from Israel's US ambassador, Ron Dermer.
"Israel is trying to accentuate the positive right now and not get into arguments with the administration," says David Makovsky, who advised the Obama administration on Israeli-Palestinian negotiations.
"But if this becomes a trend, I think Israel is likely to take a different tone."
On settlements, President Trump has moderated the tone of Candidate Trump, who said Israel should keep building.
Observers are beginning to expect a policy similar to that of George W Bush, which translated into building in settlement blocs that are expected to become part of Israel in a peace deal, but not outside them.
In this shift Mr Trump seems to have been influenced by his consultations with Sunni Arab leaders. They cannot tolerate an Israeli construction binge in the occupied territories but have quietly found common cause with Israel in a shared desire to combat the Islamic State group and to counter Iran.
It is a covert partnership on which Mr Netanyahu wants to build more overtly, and may seek US help to do so, says Mr Makovsky.
The potential for wrapping Israeli-Palestinian issues into a regional security arrangement is a long shot, although not too far from where the State Department under John Kerry left off.
And it seems to appeal to the billionaire businessman, ever seduced by the prospect of clinching the "ultimate deal".
The White House has said that Mr Trump "hopes to achieve peace throughout the Middle East".
It was a sentiment he underlined with this comment in a recent interview: "Maybe there is a chance for an even bigger peace than just Israel and the Palestinians."