A person can be a pacifist, see pacifism

Otherwise, "pacifist" is an Atari ST emulator for dos. Other emulators like gemulator use aditional hardware to emulate the Atari system, and aren't true emulation

Each Atari emulator needs the Operating System originally used on the emulated systems. In this case a version of the TOS is needed, via a ROM.

With a proper setup Pacifist can run most Atari software. Unfortunately, it's not used as Winston or gemulator provide good Windows alternatives.