Detect by whom? Deter whom? Retaliate how quickly?
If we are to deter 1st rank countries that have capable defensive forces then an SSBN would appear the better option as it can avoid detection and it has penetration ability and penetration aids. At the moment the ICBM has the best chance of reaching any target.
If a SLCM was selected instead of an ICBM then a case could be made for ALCM instead as SLCM has limited range and therefore limited reach in a given time scale although an air-breather is vulnerable to an air defence system.
Against a 3rd rank country you could use an IRBM from a tramp steamer.