With a PC it's easy for an attacker to modify the hardware, for example by inserting a recording device in the keyboard connector, so preventing an attacker fro

With a PC it's easy for an attacker to modify the hardware, for example by inserting a recording device in the keyboard connector, so preventing an attacker from modifying the bootloader wouldn't add much security. Even with a typical laptop it's fairly quick and easy to replace or insert components. In general, it's funny how security bods sometimes worry about attackers modifying the hardware when the attacker could achieve the same thing more easily by completely replacing the hardware. (Is that really your phone that you just entered your passcode into, or is it an identical phone modified so as to transmit the passcode to the thief who just substituted one for the other?)