Secretary-General Annan is in a tight corner. He wants to help Lebanon, where the United Nations is a big-league player. But he mostly values political stability, and furthering Syria’s isolation might lead to the fall of the Assad regime and to an extremely volatile situation in the region.

Hoping to lower the volume, Mr. Annan is frequently on the telephone with President al-Assad, as well as with Prime Minister Siniora of Lebanon. But the recent killing of an outspoken critic of Syria, the publisher Gebran Tueni, has raised the anger level in the streets of Beirut. Many now believe, as Tueni wrote shortly before his assassination, that Lebanon could never be free as long as the Baathist regime remains in power in Damascus.

In an ironic twist, the Tueni-owned newspaper, an-Nahar, was turned down for an interview with Mr. Annan shortly before the bombing.

The newspaper’s managing editor, Edmond Saab, sent an e-mail requesting the interview, he told me yesterday. He was willing to fly to New York to conduct it, but the United Nations wrote back saying he could only interview the undersecretary general for political affairs, Ibrahim Gambari. Since Mr. Gambari had just returned from the region, the interview was not worth it for the newspaper.

Mr. Annan’s spokesman, Stephane Dujarric, told me yesterday he did not remember an-Nahar’s e-mail, which he said was one of hundreds of interview requests the secretary-general receives all the time. He did remember, however, that a senior former official in Turtle Bay’s public information department, Samir Sanbar, who is Lebanese, made an attempt on behalf the newspaper to set up the interview.

“I tried to help the U.N.,” Mr. Sanbar told me.

It could very well be that the refusal occurred simply, as stated, because of constraints on Mr. Annan’s time. But considering the prominence of the Lebanese desk at Turtle Bay, the more likely explanation was that cautious voices in Mr. Annan’s office were concerned about appearing to favor a newspaper that so boldly spoke out against Syria’s meddling in Lebanon.

Either way, those in Lebanon who oppose Syria’s meddling increasingly turn to Turtle Bay for help.

Last week, Mr. Siniora sent a letter to Mr. Annan, requesting that the Security Council widen the scope of its Hariri investigation to include other suspected political assassinations, including the Tueni killing. This would be a move in the right direction: the international involvement in Lebanon could no longer be confined to the February 14 Hariri killing.

With armed militias assuring that explosives are readily available, and as Syrian intelligence still pulls the strings, those who killed Hariri can too easily continue their fear campaign. The Lebanese people increasingly point to Syria as the ultimate culprit in Hariri’s killing and those that occurred since.

“Yes, the Syrian authorities,” the German investigator who heads the U.N. probe into the Hariri killing, Detlev Mehlis, told the pan-Arab daily Asharq al-Awsat over the weekend, when asked if he thought Damascus was behind it. Mr. Mehlis, however, was not as explicit about this suspicion in his latest report to the Security Council, where he did not identify suspects involved in the killing.

Mr. Mehlis has told Mr. Annan that he would no longer head the investigation, which now is authorized by the Security Council to continue at least until June. He worked under difficult conditions, away from his family, and in an environment where his own life was increasingly imperiled.

His investigation also ran into some problems as one witness, Hossam Taher Hossam, recanted his testimony. The veracity of another witness, Muhammad Zuhair as-Sadiq, was shaken when traces of his DNA were not found in a room where he said he had heard Syrian officials talk about the Hariri killing.

Mr. Mehlis, I am told, is frustrated by constant second-guessing from Mr. Annan and his close advisers. In an earlier report, the names of al-Assad family members were deleted at the time Mr. Mehlis was in Mr. Annan’s office. Fearing a replay, Mr. Mehlis might have chosen simply to avoid saying in his latest report what he told Asharq al-Awsat.

It is time to shift gears. As long as Damascus refuses to let go of Lebanon while the United Nations plays favorites with the al-Assad regime, the bombs in Beirut will exact their bloody toll.