There are some keyboard shortcuts but you cant play without a mouse as far as I know, I copied this from detailed how to play instructions.
View - 'V' key + left mouse button + mouse move
Zoom - mouse wheel, middle button + up/down, zoom buttons, numpad +/-
Spin - 'S' key + left mouse button + mouse move
Fine Aim - CTRL + left mouse button + mouse move
Aim - Left mouse button + mouse move
Shoot - Right mouse button + mouse move or space + mouse move
Elevate - 'E' key + mouse up/down
Move - 'M' key + left mouse button + mouse move
Pan - 'SHIFT' key + mouse move, or arrow keys ←→