How can Morse code save lives ?

There are many ways that the ability to communicate with Morse code could save someone in an emergency or desperate situation.

For instance, a person trapped in a collapsed structure could tap out Morse code on two different materials (always starting with SOS would make it clear which were dits or dahs). This might have helped some of the survivors of the world trade center disaster. This could also work in a cave or mine.

Sometimes line of sight signaling will allow messages to be private, as was critical in the movie "Hunt for Red October" when one sub sent messages to the other by flashing a light on its periscope.

Signal mirrors, flashlights, smoke signals, especially "hash transmitters" can send lifesaving signals long distances. Imagine Chuck Nolan in "Castaway" having a good signal mirror and sighting ships or planes on sunny days.

If there is a telephone line available, even without a microphone, you can still communicate by rubbing the bared wires together.

If you've made a "hash transmitter", you probably have a limited power source. So if you have a sextant or GPS device you could transmit your location, instead of hoping to be able to transmit long enough for rescuers to find you by RDF.

Morse's value is so underated that I suggest you point out to anyone you have influence with that it SHOULD be required in amateur radio licensing, for members of rescue services such as fire and police forces, and the military.
There's no reason for nearly EVERYONE to not learn Morse code, because there is such an EASY way to do it !  It's as easy as the so called "phonetic alphabet" used by police and military, where there is a word beginning with each letter. You just need the RIGHT set of words! THESE are the phrases, of the "phonetic alphabet" that have the codes embedded in them:
Alpha,   Buffalo nickel,   Cnn,   Day time,   Echo,   Fin,   Gigaton
Hi i,   India,   Jam,   King tang,   Lair,   Mike
November,   Optomist,   Pan,   Queen may,   Reno,   Sieze,   Tango
Urea,   Via,   Wembledon,   Xname,   Yon mill,   Zero miles
These ARE the only mnemonics you need to know the letters of Morse. For instance, Jam has AM after the J. And the codes for A and M are .--. which is the code for J. Also, there are only 6 basic letters (1 or 2 buzzes) from which the others are put together. They are I..  M-- E. T-   A.- N-.

But if you want the system, how to quickly extract each code from it, and how to memorize it quickly explained in more detail, for $7 you can buy your own copy of the instructions here.

The more people that know Morse, the more potential "ears" there are to pick up distress signals. Any ordinary AM radio is capable of picking up signals from a "hash transmitter". And it is possible to make super efficient "crystal sets" which work without any power source other than the signal itself. This might be critical in the event of widespread power failure, as in case of large scale disasters. In the early days of radio, hams often played critical roles in these circumstances.
4th Edition 2011-2014