CNN's Feds send first emergency message test to cell phones describes the system and includes simple explanations like:
It's called the "presidential alert," but the President doesn't actually write it. Instead, FEMA officials confer with other government agencies and the White House, select one of several pre-written messages, customize the message to fit the particular emergency and send it out.
"The President will not originate this alert, say, from his mobile device," a senior FEMA official told reporters on Tuesday. "You would not have a situation where any sitting president would wake up one morning and attempt to send a particular message."
FEMA officials use a device that's "very similar to a laptop computer," the senior FEMA official said. After filling in the message form, two other FEMA officials are asked to sign off on the alert -- a system designed to prevent false alarms, like the incorrect alert of an incoming missile that roused and terrified people in Hawaii earlier this year.
"Everything is secured, password-protected and then authenticated or checked by two people before that message is sent," the official said.
In the post-covfefe era there is some pushback against the system, possibly in part because of the word "Presidential" in the (nick?)name of the system. Lawsuit seeks to stop FEMA's "Presidential Alert" system to cellphones citing First Amendment violation
These explanations assume everyone acts as they are supposed to act. For example who does the asking in "two other FEMA officials are asked to sign off on the alert"? Do the issuer and both other officials each use a separate secret password, or is the issuer simply supposed to ask them for their approval? Do they all have to be in the room or access this one device in order to authorize, or can at least the two "authorizers" do that from home/remotely?
Question: How is the US' "Presidential Alert" safeguarded against inappropriate or unauthorized use?