https://travel.state.gov/content/travel/en/international-travel/emergencies/what-state-dept-can-cant-do-crisis.html 6park.com

Will the U.S. government pay for my evacuation if it is needed?
No, U.S. law requires that the assisted evacuation of private U.S. citizens or third country nationals be provided “on a reimbursable basis to the maximum extent practicable.” However, we do understand that you may not be able to access your own money during a crisis. For evacuation transportation that we arrange to transport you out of a crisis location, you do not have to pay before you board. To board these transports, you will need to complete and sign a form promising to repay the U.S. government. The amount billed to evacuees is based on the cost of a full fare economy flight, or comparable alternate transportation, to the designated destination(s) that would have been charged immediately prior to the events giving rise to the evacuation. Because different evacuation transports may go to different destinations, the cost of one transport may be different than another. We encourage people to leave on the first transport they are able and eligible to board.
As mentioned above, an evacuation is almost always to a nearby location away from the crisis, which is very rarely to the United States. You are also responsible for the costs you may incur in the destination, including hotel, food, clothing, medication, and other necessities.
Emergency financial assistance in the form of a loan may be available to U.S. citizens who are unable to pay for their onward travel to the United States.