C172 pilot reported that they observed an unreported unlit military helicopter on the runway while on approach at night to a non-towered airport which resulted in a go around and a critical ground conflict event.

Narrative

Normal night flight into ZZZ resulted in near miss with non-vocal military helicopter. Helicopter pilot never announced position. During the approach; visibility of the other aircraft was severely limited due to the lighting and environmental conditions. The helicopter was completely blacked out with no external lights illuminated. The runway itself was equipped only with edge lighting and had no centerline lighting or other sources of illumination that would have provided additional contrast.At approximately 200 feet on short final; my outside visual scan was focused on maintaining runway alignment and glidepath using the available edge lights. Under these conditions; a dark; unlit helicopter positioned on or near the runway surface would have presented almost no visual contrast against the surrounding pavement. A spinning rotor system without lighting provides minimal visible cues; and the lack of centerline lighting removed the primary backlighting that would normally help reveal an obstruction.Given the limited contrast; night visual limitations; and the absence of lighting on the helicopter; detecting it visually at that distance would have been extremely difficult and likely not possible until very close to the obstruction. This created a situation where timely avoidance would have been highly unlikely. I performed a go around immediately after I was able to distinguish what I was seeing on the ground.