  We compare the prospects for observing theories with Majorana or Dirac
gauginos at a future 100 TeV proton-proton collider. Calculating the expected
discovery and exclusion regions, we find that for heavy gluino masses the
squark discovery reach is significantly reduced in Dirac gluino models relative
to the Majorana case. However, if the squark and gluino masses are close the
reach is similar in both scenarios. We also consider the electroweak fine
tuning of theories observable at such a collider, and the impact of existing
constraints from flavour and CP violating observables. Models with Majorana
gluinos that are fine tuned to less than one part in 10,000 can typically be
discovered or excluded, and Dirac models with tuning of one part in 1,000 can
be probed. The flavour structure of Majorana models is highly constrained if
they have observable squarks, while O(1) violation is possible in accessible
Dirac models. In both cases new sources of CP violation must be very
suppressed. Future collider searches can also give important information on
possible dark matter candidates. We study the relation of this to indirect and
direct detection searches, and find that if dark matter is a neutralino, a 100
TeV collider could probe the viable dark matter candidates in large classes of
both Dirac and Majorana models.
