Macau has barred entry in recent days to a number of Hong Kong residents, including a university dean, several politicians and a photojournalist for the South China Morning Post.

Now a lawmaker in Hong Kong is suggesting the port city should reciprocally bar entry to some Macau residents.

The right foot and left foot are angry with each other.

It is a strange spat. Until recently, Macau was a rather sleepy place, a former Portuguese colony that reverted back to the mainland’s control in 1999. It’s a 45-minute ocean ferry ride away from Hong Kong, the throbbing global trade center. For all of Hong Kong’s worldliness, Macau is a great little place, with wonderful Portuguese food and lots of colonial-era architecture. Both cities are former colonial appendages now under Chinese supervision.

Money has poured into Macau. Several big U.S. gaming companies have moved in, letting Macau surpass Las Vegas in gaming revenues. Lots of the gamblers are from Hong Kong.

An election battle is under way to succeed Edmond Ho as Macau’s chief executive, the post that is the nominal governor of the autonomous region.

The speculation is that politics has something to do with why Macau border officials are turning away prominent Hong Kongers – three of them in the past week. Maybe some security people are trying to embarrass Ho and his favored candidate, or maybe Macau is trying to curry favor with hard-line honchos in Beijing.

Last Friday, Macau rejected the entry of Johannes Chan, dean of the law faculty at the University of Hong Kong. Chan, a former head of the Hong Kong bar association, was to give a lecture at the University of Macau.

On Tuesday, they turned back pro-Democracy activist Bruce Liu Sing-lee. A few days earlier, they barred Frederick Fung Kin-kee, also a democracy activist. Late last month, South China Morning Post photographer Felix Wong was turned away.

Chan told reporters he suspects his opposition in 2002 to a rather Draconian security law in Hong Kong was what led to the action. Hong Kong rejected the proposal but Macau passed a nearly identical proposal last week, and it went into effect Tuesday. The law prohibits treason, secession, sedition, the theft of state secrets and subversion against the Beijing government.

Hong Kong's security chief, Ambrose Lee, said Thursday he would seek an explanation from Macau about the travel bans. He said he was “concerned.”

Stanley Ho, the Macau gambling tycoon, who is close to both Chinese and U.S. security officials, and has operations in North Korea, lauded Macau border guards, saying the Hong Kong residents denied entry were all “troublemakers.”

Albert Ho, a Democratic Party representative to the Legislative Council in Hong Kong, said he favored Hong Kong taking reprisal action and barring some Macau officials entry.

From what I hear, Beijing is a bit worried about Macau. The gaming industry has been slammed by the global downturn, and unrest among the growing jobless ranks could grow. Beijing is stonewalling a U.S. request to open a consulate there to look after U.S. interests, worried that U.S. diplomats would actually stir up trouble.

But with Macau’s sweeping new security law, I don’t see why they’d be worried. The law provides for the arrest of anybody its leaders view as troublemakers.