If the U.S.-China trade war takes a particularly nasty turn, a possible target for Beijing could be the multiple American-operated casinos in the tiny gambling enclave of Macau.

Such a move, however, is highly unlikely, according to one analyst who follows the Asian gaming sector. The reason, according to Jonathan Galligan, head of Asia Gaming and Conglomerates at CLSA: the U.S. casinos have played an important role in helping China achieve its economic development goals for the former Portuguese colony.

Macau was ruled by Portugal for more than four centuries before being returned to China in 1999. Like nearby Hong Kong, which was a British colony for a century and a half but returned in 1997, Macau is now a special administrative region of China.

U.S. President Donald Trump is threatening Beijing with tariffs potentially covering the entire amount of Chinese exports to the U.S. as he seeks to reduce his country's deficit in goods and extract concessions on other bilateral flash points such as technology and intellectual property. China, for its part, has responded with its own tariff threats, but its large trade surplus means it can't match the U.S. tit for tat.

That has led to speculation it might seek to apply pressure on the U.S. in other ways, such as making it more difficult for American companies doing business in the country.