HONG KONG — North Korea is one of the world’s most isolated countries. It is ruled by an unpredictable dictator with his finger on the nuclear button. So, who’s ready to do business there?

Well, basically nobody.

But leading up to President Trump’s meeting in Singapore with Kim Jong-un, which concluded on Tuesday with a deal to keep talking, some intrepid businesses and investors began considering the possibilities. What happens if North Korea opens its economy, even just a little, giving global businesses a shot at East Asia’s last untapped growth market?

Mr. Trump on Tuesday dangled visions of what North Korea could win if it abandoned its nuclear weapons and changed its ways.

“As an example, they have great beaches,” he said at his news conference after the summit meeting. “You see that whenever they’re exploding their cannons into the ocean. I said, ‘Boy, look at that view. Wouldn’t that make a great condo?’”