what does it mean?
something at which one excels; forte
im very good at cooking, so cooking is my strong point.
we can say this about a millitary area where they guard it well, so no enemy can penetrate this place because it's a strong point.
also when a lawyer is looking for evedince to prove someone's innocence and finds something useful to defend him, he says that's a strong point in our defence.
Tom: i was at the shop at the time of the murder and the shopkeeper saw me
Lawyer: that's a strong point in our defence.