Why cargo and commercial ships should shift to NUCLEAR POWER ENGINES like what it is used in US NAVY ships

Several reasons, including:
Lower cost fuel. At current prices, reactor fuel costs 85 percent less than bunker fuel.
Zero emissions. In crowded port cities, air pollution laws are becoming more stringent and costly.
Concentrated fuel. Nuclear reactors can be built with fuel supplies lasting for many years.
High power to weight ratio. Merchant ship owners are increasingly interested in rapid transits over long distances.

What happens if an atomic powered ship is in a collision or sinks?
Any collision or grounding is bad, but we can use the accidental experiments of the nuclear navies to show that they are no worse for nuclear powered ships. The cores of an atomic engine are carefully designed and constructed to prevent the release of radioactive material under all conditions and there are at least three barriers between the material and the environment. So far, there have been no measured radioactive material releases from the cores that are currently on the bottom of the ocean