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Joe Biden may not have envisaged his first major foreign policy challenge would also become a key test of his ability to lead his party.
But with the outbreak of violence in the Middle East, the US president has found himself increasingly at odds with many of his fellow Democrats over his support of Israel.
For days, Mr Biden has publicly backed Israeli Prime Minister Benjamin Netanyahu over his military response in the Gaza Strip.
The US president is acutely aware of the potential political fallout of appearing to weaken America's commitment to Israel.
But on Capitol Hill, a prominent group of Democrats has become more vocal than ever in criticising Israeli military actions, linking the issue to America's own racial and social justice debates.
The strongest pushback has come from the most progressive members of Congress, chief among them the firebrand congresswoman Alexandria Ocasio-Cortez, who went as far as to call Israel an "apartheid state".
This group of liberal Democrats has made no bones about publicly breaking with their president over the matter.
During a trip to Michigan this week, Mr Biden found himself being confronted by Democratic congresswoman Rashida Tlaib as soon as Air Force One hit the tarmac.
Ms Tlaib, the first Palestinian American woman to serve in Congress, appeared to spar with Mr Biden for several minutes ahead of his speech at a Ford car plant.
Keen to keep his party united, Mr Biden singled out Ms Tlaib when he later addressed the crowd, praising her as a "fighter" and assuring her he would "do all I can" to ensure her family in the West Bank remained safe.
But the growing criticism of Israel's actions goes well beyond the progressive flank of the Democratic Party. A broader shift in the party's stance was clear when senator Bob Menendez, one of Israel's staunchest Democratic allies, issued a sharp rebuke of the country's missile strikes.
The evolving attitudes appear to be mirrored in the wider public, with a recent Gallup poll finding Americans' support for putting pressure on Israel was at a new high of 34 per cent.
While the February study found the majority of Americans still strongly support Israel, the public's sympathy towards Palestinians had also grown to a new high of 25 per cent.
Mr Biden had hoped to focus his efforts on confronting China and Russia, rather than becoming embroiled in a yet another Middle East peacemaking attempt which is unlikely to yield him much dividend.
But with political pressure increasing at home and abroad, Mr Biden has found he can no longer avoid further inserting himself into the conflict.
In his most direct message yet, he warned Mr Netanyahu he expected to see "significant de-escalation" of the fighting during a phone call on Wednesday.
But with Israel insisting it will push ahead with the Gaza operation "until its objective is achieved", progressives in Congress have shown they are willing to take further action.
A resolution opposing the sale of $735 million in military weaponry to Israel previously approved by the Biden administration was put forward on Wednesday.
It is merely a symbolic move, but those behind it say they intend to send a message to both Mr Netanyahu and Mr Biden: you can no longer rely on our unwavering support.