This is a metaphorical sentence. However, you should use 'in' instead of 'with': Wrap A (up) in B / Wrap B around A = The king wrapped this country up in the clothes of immunity. Or The king wrapped this country in a garment of immunity. Or The country is wrapped up around a garment of immunity.

I think the king has made his people strong - a citizen that will not easily be slaved by other kingdom or perhaps, a citizen who will not easily give up in a battle in keeping the glory and honor of their kingdom... the sentence on the other hand, looks metaphoric to me in which "wrapped with the clothes" would simply mean to "protect". :)

its like a country under iron curtain i guess. cowboy...