The war between Israel and Gaza comes at a moment of historic chaos in the US Congress, where Republican infighting risks hampering the US response as Washington rushes to support its ally Israel.
Most pressing is the fact the House of Representatives has no way to bring forward legislation to approve new spending for Israeli security, after Kevin McCarthy was removed from his position as speaker by his own Republican Party last week.
The earliest that Republicans, who hold a narrow majority, can try to install a new leader is on Wednesday.
House foreign affairs committee chairman Mike McCaul told Fox News on Monday that the US has “adequate” funding to support its response to the war “in the short term".
But Mr McCaul said that Congress must act to ensure longer-term support to Israel, including replenishing its Iron Dome anti-missile system and its supplies of precision-guided missiles.
“I would urge my colleagues to not play games with this. It is very serious. It sent a message to the rest of the world that we are weak and dysfunctional,” he said.
“Democracy has to work right now. The world is simply too dangerous.”
Israel has launched a barrage of strikes on the densely packed Gaza Strip, vowing a “complete siege” including “no electricity, no food, no fuel” in response to Hamas militants' surprise attack that has killed at least 900 people in Israel.
More than 500 Palestinians have been killed since the war's launch.
At least nine Americans are among the dead.
Defence Secretary Lloyd Austin said on Sunday that the US military will immediately start shipping ammunition to the Israel Defence Forces.
The House of Representatives has a temporary Speaker, Patrick McHenry, but he has only limited authority and is unable to bring forward legislation until a permanent leader is elected.
He does not have the power to issue subpoenas or sign off on any other official House business.
The Congress had already appropriated $3.3 billion for assistance to Israel, which President Joe Biden has full authority to take from.
“It's absolutely essential we elect a speaker and get back to the business of the people. The first bill on the floor will be my bill condemning Hamas for this terrorist assault on Israel,” Mr McCaul said.
Jonathan Lord, senior fellow and director of the Middle East security programme at the Centre for a New American Security, said the House was going through “unprecedented times”.
Mr Lord said that rules are “opaque” regarding Congress's ability to act on increasing support for Israel without a speaker of the House.
Mr Biden “is going to need more support in the form of a supplemental [spending approval] once he's either exhausted the US stock supply or feels he can't deplete it any further,” Mr Lord, who previously worked on the staff of the House armed services committee, told The National.
He believes with strong enough bipartisan support to push relevant legislation through, Mr McHenry “could get legislation passed to support Israel in this conflict … but the adults in the room need to prevail".
“Checks and balances require the US Congress to function. If it doesn't function, things go bad really fast even before we get to these types of crises," he said.
"If the Congress can't get itself into a position where it can enact legislation, that's detrimental in massive ways.”
Already, the usual order of business for moments of crisis has been disrupted in the Congress.
Democratic minority leader Hakeem Jeffries was reported to have been briefed on the war on Saturday, and is expected to schedule a briefing for all House members next week.
Typically, the speaker of the House would have received that briefing.
But the war has rallied strong bipartisan shows of support for Israel in Congress, and Mr Biden and Israeli Prime Minister Benjamin Netanyahu have been in frequent contact, seemingly setting aside political differences for the moment.
Senate foreign relations chairman Ben Cardin said he intended to advance legislation “at the first opportunity” that boosts US military support of Israel, including “replenishment of missile defence for Iron Dome that ensures such interceptors are always available".
Meanwhile, the war appears to have expedited the stalled confirmation of Mr Biden's nominee for ambassador to Israel, Jack Lew.
US media reported on Monday that the Senate foreign relations committee will host his confirmation hearing on October 18.
Defence Secretary Lloyd Austin on Sunday also ordered the USS Gerald R Ford aircraft carrier strike group into the Eastern Mediterranean in support of Israel and to deter Hezbollah in Lebanon.
The US and Israel trained together in January during the allies' largest ever joint military exercise, Juniper Oak.