The killing of the Libyan rebel military commander, Gen. Abdul Fattah Younis, suspected of working for Moammar Gadhafi despite abandoning the Libyan leader in February, is an ominous and embarrassing development that raises further questions about the ill-prepared NATO intervention.

The haste with which the West has embraced the Transitional National Council (TNC), which now has access to frozen Gadhafi regime assets and is setting up embassies in London and Paris, is staggering considering that the rebels were an unknown quantity only months ago. The TNC was recognized by Washington last week as the legitimate government of Libya.

The West’s earlier lack of knowledge about the Libyan opposition is an indictment in itself. What were the CIA and MI6 doing in Libya if they were unable to inform their political masters about the potential opposition to Gadhafi? Were they so certain that the dictator would remain in power until his death? It was probably the same “credible channels” that fed British Foreign Secretary William Hague the wrong information last February that Gadhafi was on his way to exile in Venezuela.

The rebels themselves apparently had doubts about the allegiance of Younis, who had been part of Gadhafi’s inner circle before he defected to great fanfare. Did NATO share those doubts?

But the killing of Younis, along with two aides, will focus an unwelcome spotlight on the conduct of the rebels, who, far from being the country’s best hopes for democratic rule, have now been accused of human-rights atrocities by none other than one of their principal cheerleaders, Sen. John McCainJohn Sidney McCainCummings to lie in state at the Capitol Elizabeth Warren should concern Donald Trump 'bigly' Lawmakers toast Greta Van Susteren's new show MORE (R-Ariz.).

In a letter to TNC head of foreign affairs Mahmoud Jibril seen by my former colleague Kim Sengupta of the London Independent, McCain points to a damning report by Human Rights Watch and urges the rebels to “bring any human-rights abuses to an immediate halt.”

"I urge you to investigate recently documented abuses, hold people accountable as necessary, and ensure that opposition military forces are abiding by the principles of justice and human rights,” said McCain in the letter dated Wednesday.

In Libya, a country divided along tribal lines, civil war was always a danger. Younis’s killing means that danger is even more real.