Pentagon spokesperson Patrick Ryder speaks during a briefing at the Pentagon in Washington, on August 24, 2023. (AP)

Four people with knowledge of US government contingency planning say that the Biden administration is bracing itself for the potential that hundreds of thousands of citizens will need to be evacuated from the Middle East if the crimes in Gaza cannot be stopped.

The possibility of such an operation exists as Israeli forces, supported by military advisors and weapons from the United States, prepare for what is anticipated to be a dangerous ground invasion against Hamas.

Speaking anonymously to discuss internal discussions, the officials stated that Americans residing in "Israel" and neighboring Lebanon are a particular source of concern. However, they emphasized that such an evacuation is viewed as the worst-case scenario and that other consequences are more likely.

Still, according to an official, it "would be irresponsible not to have a plan for everything."

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According to three people familiar with the discussions, the administration is extremely concerned about possible escalations despite its strong public support for "Israel". In recent days, it has focused on the challenging logistics of suddenly relocating a large number of people.

According to State Department estimates, there were around 600,000 American citizens in "Israel" and an additional 86,000 thought to be in Lebanon at the time of the Hamas attack.

Beyond those two nations, the administration is concerned about the street protests that have extended throughout the Arab world, endangering US residents and personnel stationed there.

The shelling of Gaza has stoked anger in the region toward "Israel" and the way it treats Palestinians, a subject that some leaders thought was less significant in the Arab world.

'The People are now in charge'

As per Bruce Riedel, a former official in the Clinton administration and presently a senior fellow at the Brookings Institution, "The street to a large extent is now in charge."

"We were told for the last 10 years that the Arab world and Muslim world didn’t care about Palestine anymore, and Abraham Accords were proof of that," Riedel added, talking about agreements, signed by Bahrain, Sudan, Morocco, and the United Arab Emirates. "Well, Palestine has come back. I don’t think it ever went away."

Top US authorities avoided talking about such emergency preparations in public, to prevent panicking US citizens living in the area. However, in recent days, their stance has shifted to reflect their unease about others joining the fight.

Last week, the State Department issued an advisory to all US citizens worldwide "to exercise increased caution" due to "increased tensions in various locations around the world, the potential for terrorist attacks, [and] demonstrations or violent actions against US citizens and interests."

The warning came in response to protests that broke out over the Israeli aggression on Gaza and to a general outcry among Arab nations over Washington's political, economic, and military support of "Israel".

Experts warned that a possible US evacuation may be more complicated than any in recent memory, depending on its scope. It might involve the Navy's vessels or Air Force planes, which have been moving into the area this month.

The Pentagon also made a signal on Monday, indicating that it is ready for a major uptick in attacks against US forces in the Middle East. The Pentagon specifically mentioned Iran for its widespread support of organizations that have a track record of utilizing drones and rockets to target US military installations. Officials from the Pentagon stated that in response, they are deploying more missile defense systems to the area.

Read: As 'Israel' bombs Gaza, US worries about its troops in Middle East

A Pentagon spokesperson General Patrick Ryder told reporters that a "broader escalation" is possible "in the days ahead," adding that senior military leaders are taking "all necessary measures" to safeguard US personnel.

The estimated 3,400 troops stationed in Iraq and Syria are particularly susceptible; earlier in the day, according to officials, US personnel stationed close to the Jordan border intercepted at least two one-way attack drones. The Islamic Resistance in Iraq claimed responsibility for some of the prior attacks made public during the past week.

The number of incidents in which deployed soldiers have been targeted since the launch of Operation Al-Aqsa Flood started on October 7 is unknown. The Pentagon was assembling a list of proven occurrences, according to officials, but the process had been impeded by what one senior defense official referred to as the abundance of "disinformation and misinformation."

Last week, when soldiers and others at the Ain al-Assad air base scrambled to take shelter from what turned out to be a false alert of an impending target, one American contractor in Iraq suffered a deadly heart attack.