What does the US Coast Guard do that the Navy and the Marines can’t do?

Question

I’m not from the US and have no military experience either. So the US has apparently 3 maritime branches in the uniformed services and the Coast Guard is, well guarding the coasts of the US. And the other branches can’t do that?

In: Other

Answer 1

I was in the Coast Guard and in my time I was first a deckhand on a polar icebreaker that went to the north and south poles and then I was an MST who flew all over the place in Alaska responding to oil spills. The Navy does not do these things.