Undoubtedly, one of the last things an incumbent president would like to hear of is his lapse, be it ongoing or imminent, into lame-duck status. Who would? Actually, President Lee Myung-bak was previously quoted as saying there would be no such thing until his last day in office.

But it is a matter of time before a rapid decline in the presidential power manifests itself in various forms. It usually starts to come around the fourth year of the presidency, with the president constitutionally banned from pursuing a second five-year term.

One lame-duck manifestation for President Lee was the ruling Grand National Party’s revolt against his nomination of one of his former aides as chairman of the Board of Audit and Inspection, the state watchdog. Instead of endorsing his selection, the party recommended on Monday that the nominee, the former senior prosecutor Chung Dong-ki, withdraw himself before a confirmation hearing started in the National Assembly.

More symptoms will surely come in the run-up to the termination of his presidency in February 2013. One of the most humiliating among them could be a decision by the very party that elected him to the presidency to oust him should he be considered a liability rather than an asset during the next parliamentary and presidential elections, both scheduled for 2012.

Lee will do well to prepare himself to accept such mortification with magnanimity. He would be neither the first nor the last to leave his party under pressure. Actually, all of his four immediate predecessors had to renounce their party membership against their wishes.

On being informed of the ruling party’s decision to withdraw support for Chung, one of the senior presidential secretaries was quoted as saying, “Is it meant to tell the president to leave the party?” Even if it isn’t, the relations between the presidential office and the party will hardly be the same as before.

The opposition Democratic Party was vociferous in its opposition to the nomination. It claimed Chung would be subservient to the president, instead of being politically neutral, should he take the post, given that he served Lee as his top aide for civil affairs in 2008-09. Moreover, the enormous amounts of money he took in monthly salaries from a law firm after retiring as a senior prosecutor in 2007 was painted by the opposition as a typical case of the favoritism accorded to those fresh from their service as a prosecutor or a judge.

Chung may not have breached the law in pursuit of his personal gain. Finding that the opposition party’s boycott was winning public support, however, the ruling party decided to demand Chung withdraw from the nomination. The ruling party’s sensitivity to a shift in public sentiment is understandable, with parliamentary by-elections scheduled for April. It cannot lower its guard ahead of the elections, which may turn out to be a prelude to the 2012 general and presidential elections.

As hindsight shows, the presidential aides that vetted Chung’s background were shortsighted when they did not report to the president the potential implications of his nomination to a post that demands political neutrality and autonomy. As such, they may deserve to be held accountable for their poor work. But the ultimate responsibility lies with the president himself.

What the president needs to do now is honor the ruling party’s decision and start the process of selecting a nominee all over again. He will have to take extra care this time because he cannot afford to make another mistake.

Separate from this immediate task, he will have to start setting priorities on the projects he wishes to accomplish during the next two years. Preferably, he will focus on wrapping up the projects that he has launched rather than launching new ones.