Ethical issues can be subjective, but the government has to make ethical decisions about certain things. Every country has laws against murder, rape and so on. There are certain things that the government should make illegal. In my opinion, ivory trade is one of these things. Many people and countries recognize this as wrong.
It is a government's responsibility to determine whether the trade of certain materials is ethical with help from citizen's opinions. A country's government is the one body has control over the country's activities, and if popular opinion is that trading a certain material is unethical, the government should ban that trade.
Hong Kong has a moral repsonsibility to figure out if luxury goods are unethical. In this case, it is definitely unethical. The underground market for elephant horns is of epic proportions and funded by criminal syndicates. Hong Kong is doing the right thing by banning this as at this point in time.
Due to Hong Kong's role as an international leader in the global marketplace it is now taking steps to reduce its footprints in the fiercely debated ivory trade. It is no secret that Hong Kong is home to many of the wealthiest consumers in the world. Wealthy consumers often have a taste for the rare and expensive, with ivory being one of the commodities of choice.