for a Moderator? Since the opening of the IAF at SEA (May 2022), most of the process for international arrivals has changed and the intro is out of date. Maybe a new thread for posts after that date? As an example, here's info from SEA website about the current process.

International flights arrive at the airport at two concourses. If you’re flying on an international airline — you will arrive on the S Concourse. If you’re on a domestic carrier like Delta or Alaska in a narrow body aircraft — you will arrive at the A Concourse. All passengers join up at the International Corridor where they will follow the signs to enter the United States before continuing to baggage claim and customs processing. On your way to customs, you’ll enter the Welcome Portal. This is also where will find restrooms, nursing suites, baggage information systems, and Service Animal Relief Areas. Make sure to check your assigned baggage claim by your airline and origin city in the overhead signage since you’ll have to claim your bags before you enter Passport Control.

Members of Trusted Traveler Programs, such as Global Entry and NEXUS, will grab their bags on baggage claim before heading down to passport control. See more information about International Trusted Traveler Programs to help expedite your passport control process!