1) 1955 moment has happened, is happening and is going to happen: walking backwards means turning towards the past, which in this case is important in order to make a link with the present and the future.
2) We spend your life walking backwards because you can see the past but not the future—that’s why we trip: Walking backwards is a good way to concentrate on the walking as a process, on the physicality of it.
3) Be kind rewind: each step of Bandung walk is meant to symbolize the change that the conference would bring about - by performing the walk backwards we create the cavity in deep time, and the possibility/necessity for the walk to 'happen' again, to fill in the gap, thus provoking the deep time to bounce back.