Im trying to create a USB device that contains an image of kali linux that will run on a pi 3. I have already doenloaded and install the arm image from the kali site to an SD card and it boots and works great on the pi 3. My desire is to now copy the SD card to a USB device and boot the USB device. I have followed the instructions on the kali site using bot the downloaded .img file as wel as the expanded OS that exits opn the SD card. in both cases the DD seemed to work correctly (records were copied :-), hoever, the pi3 wont boot kali from the usb device. can anyone help?

Thanks, in advance.

Del Thompson