"Since the United States declared war on our country, we will have every right to make countermeasures, including the right to shoot down United States strategic bombers even when they are not inside the airspace border of our country," Ri said

The first part of Ri’s rant is meaningless, since the Korean War (which the North started) ended only as a ceasefire so the US and the DPRK are still technically at war.

As to the second part, the best response to that comes from the classic Clint film Dirty Harry: “Go ahead punk, make my day”….