How to encrypt USB drive on a Mac? I have an external USB drive and want to encrypt it. I have seen many 'suggestions' on how to do that, but I do not see any option to encrypt the drive. I am using MacOS 10.13.2.

I have see, for example, this answer. But in step 9, when I right click the drive (on the Desktop or the Finder), there is no option 'encrypt'. Before that I have formatted the drive in the 'Mac OC Extended (Journaled)' format. No option for encryption in the Disk Utility either ...

So how to do that? Maybe the option was forgotten in the new OS version?
I didn't find a way to do this from Disk Utility, but you can accomplish it from Terminal using diskutil.

Open Terminal and run diskutil list to show all devices currently connected. One of the entries should look similar to

/dev/disk7 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     FDisk_partition_scheme                        *1.0 GB     disk7
   1:                  Apple_HFS LOGBOOK                 1.0 GB     disk7s1


with the name of your USB stick instead of LOGBOOK. Take note of the device shown in the first line.

Then run

diskutil eraseDisk JHFS+ NEWNAME GPT /dev/diskWHATEVER-NUMBER-YOURS-IS


to erase all content and create the required partition scheme. Replace NEWNAME with whatever name you want to use (enclose in "" if it contains anything else than letters) and use the device number found above.

Once done you can encrypt in Finder by right-clicking on the stick name in the sidebar.