Yes, it is generally safe for Americans to drive in Costa Rica, but it requires a high degree of "defensive driving" and awareness. The main safety concern is not violence, but rather road conditions and petty theft. Many secondary roads are unpaved, prone to washouts during the rainy season, and lack guardrails or streetlights. You should never leave valuables in a parked car, even for a few minutes at a scenic overlook, as "smash-and-grab" thefts targeting tourist rentals are common. Use a 4x4 vehicle if you plan to explore beyond the main highways. Driving at night is strongly discouraged due to potholes, wandering livestock, and pedestrians on unlit roads. However, if you stick to daylight hours, use GPS apps like Waze (which is very accurate there), and follow standard safety precautions, driving is the best way to see the country's diverse landscapes at your own pace.