Final answer:
To survive, the Republican sniper most likely needed to eliminate the enemy sniper, as this removes the immediate threat and allows for securing their position, according to common military strategic practices in literature.
Step-by-step explanation:
The subject matter of the question centers around a strategic decision made by a character dubbed the 'Republican sniper'. The scenario described is about making a tactical choice in a combat situation, which can be derived from the context to be adapted from a narrative or literature piece, such as a short story or a novel about war. Therefore, to answer the question about what the Republican sniper needed to do to survive, one can infer based on standard tactics in military-themed literature:
- Retreat to a safer location if the area is too dangerous and survival chances are slim.
- Call for reinforcements if isolated and outnumbered, ensuring better odds through numerical advantage.
- Eliminate the enemy sniper to remove the immediate threat and securing their own position.
- Surrender peacefully as a last resort if the situation is hopeless and fighting on would lead to certain death.
In military strategy, the best course would often be to eliminate the immediate threat if possible. Thus, the most likely answer, echoing points from the given references, is that the Republican sniper needed to eliminate the enemy sniper to ensure his survival.