This is for the most part correct, however:
The strong Nuclear force is explained by
Quantum ChromoDynamics, or the colour interaction. The colour interaction,
QCD, is such that there are three colour charges,
red,
green, and
blue, and a proper interaction only occurs between all three when they are together.(There are no actual inherent colours and in fact they are always changing, its just that the sum of three results in neutrality)
Even more interesting, however, is that the colour force gets stronger with distance. If one were to try and extend particles interacting through QCD, he or she would find that the force between said particles would increase to infinity.
This poses a problem for those scientists who want to observe quarks, which interact through a colour charge. The quarks cannot actually be separated. The solution to this is to observe the quarks when they are very close together. Thus the force between them shall be weak. Using this priniciple, scientists were able to rattle protons and neutrons to observe their constituent quarks.