Mars is a masculine out-thrusting energy and represents the masculine facet of self. Mars is desire, if you have no desire you don't reach out to influence the external. The Mars glyph is a circle with an arrow symbolizing the spirit of humans connected to earth life.
In Libra there is an inherent dichotomy where the feminine masculine energy of the mind is affected by the instinctual and desire driven. Mars transiting Libra energizes the desire nature in relating, sex, awareness of imbalance and the need for fairness.
Mars in Libra can be persuasive, perceptive, enthusiastic, and argumentative (Libra loves debate and Mars raises this tendency an octave). This may be a time when diplomacy and patience needs to be cultivated. The desire for relating and relationship is accented.
Libra grounds in Aries and this heightens the electric and assertive energy of anger being born out of unfair relating and legal dynamics.
The higher vibration is acting as an arbitrator between warring factions, seeking common ground and feeling driven to initiate connection.