Mars retrograde is an interesting retrograde phenomenon that happens along every 2+ years or so. This one can be rather intense and jarring: Venus and Mercury deal with issues that are pleasant, and mentally challenging. But Mars, whether retrograde or direct, has us face something perhaps a bit deeper - the nature of our passions and wants and desires, and allowing the full expression of them.
Those issues will always have an emotional charge attached. Passion is a key issue for many, and so are passion's brothers and sisters = assertion, intention and anger (when passions are thwarted). The hottest buttons we have - those ones that get us fired up - are the Mars issues we have to address. In most societies, and of course, the animal kingdom, Mars has been the man's domain. It is the male of the species that protects and will fight those that threaten the family unit. Its an age-old archetypal law. Mars in the animal world is instinctual and territorial and vital - it is the survival of the fittest.
In humans, though, Mars is more about the psychological drives we have to perhaps succeed, and get what we want, beyond instinct, since we're one of the few species that has the ability to choose and to analyze one's behavior. Mars, though, is not just men, in humans, but females, too - so no one is exempt from this process. Both male and female need to integrate the nature of the Male/Mars archetype within us. If that weren't so, then women wouldn't have been born with a Mars in their birthcharts. The idea here is integration of both male and female. Most women are less comfortable with expressing their male side, as men are mostly uncomfortable about expressing their own female side. It's this integration that makes for interesting Martial expressions - some more violent - in our society.
I think Mars retrograde is a marvelous "time out" to look at how we approach getting what we want, and addressing those hot-button issues we still have. There is an intensification of the Mars principle in our lives during these times because Mars is internalized and more self-directed. I believe the idea here is learning to be proactive, not reactive. Yes, the reactive buttons will get hit, but with Mars retro, conscience and maturity will eventually win out. If we know why we react, then the ability to change that by proactively seeking answers as to the "why" of the reaction can help change negative behavior patterns forever.
With Mars in the sign of Leo, it really is about self-fulfillment, and likely we'll be meeting those people with anger about not feeling loved enough, or at the very least, acknowledged (which will be our mirror to those issues in ourselves). The ego drives will be very strong. Anger about the thwarting of these drives will likely surface, and must perhaps be redirected in finding arenas of self-expression that will add to the person's life - and not blaming others for why it hasn't worked in the past.
Mars in Leo, retrograde, can really dig into the childhood issues of perhaps why it might have been unsafe to express those anger issues that kept the creative self expression curbed. It's all manner of possibilities of change with Mars. It will be what it is for the native, and during this next two month period, it could be a real awakening for the creative spirit within us.
