By Gordon Corera
BBC security correspondent
New CIA director Porter Goss is proving controversial
The widespread reports of turmoil within the Central Intelligence Agency (CIA) centre on its new director, Porter Goss.
An ex-Republican Congressman who was confirmed in the job shortly before the presidential election, Mr Goss has arrived at CIA headquarters in Langley, Virginia with a very clear agenda.
In his view, change is needed after a series of intelligence failures, most recently over Iraq's alleged weapons of mass destruction (WMD) programme.
But his plans have reportedly met with resistance from long-serving senior officers. Some of them have left the agency and others have threatened to leave.
There is no doubt that Mr Goss is a man of strong views. When I interviewed him earlier this year, before he was nominated to run the CIA, he made clear that he thought the Agency had failed in its "core mission".
"The core business of intelligence is spying", he told me. "That means close in access to the hard targets. That means a lot of risk.
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In his view, it needed "clandestine officers who know how to run agents into hard target areas, all of the people skills, all of the tradecraft skills that go into this.
"Those are things we sort of let go...we suddenly found ourselves disinvesting - not just not investing - but actually disinvesting in our core collection business [in the 1990s]."
He warned that, as well as greater investment, a real shake-up was needed in the clandestine service that recruits spies, and throughout the intelligence community.
As he put it, "This is not just [about] individuals or moving chairs. Some really serious changes" were needed.
Mr Goss's supporters argue that the current tensions merely arise from the resistance of a large, entrenched bureaucracy to being told it needs to improve its act.
Other critics point to Mr Goss's reliance on a small group of aides he has brought with him from Congress who are not making themselves popular.
But the real question is whether there is an agenda to do more than reform the CIA internally, and bring it to heel politically.
Some people both inside and outside the CIA fear this may be the case. They worry that Mr Goss will use the battering that the agency took over 9/11 and Iraq to clear the decks.
Other observers say charges of politicisation are being used to undermine much-needed reform.
What is certain is that US right-wingers have grown increasingly critical of the CIA, and some have accused it of leaking like a sieve in order to undermine the Bush administration.
Information has found its way to the press which presented the CIA as being prescient about events like the Iraq insurgency, but finding itself ignored by the administration because the warnings did not fit with their agenda.
One columnist has even written that there was almost a sense that the agency was campaigning for John Kerry to win - and that this is unacceptable for a part of the US government which is supposed to stay out of politics and policy-making.
CIA officer Mike Scheuer became part of the row when his book Imperial Hubris was published anonymously over the summer.
The CIA allowed him to conduct media interviews in which he argued the invasion of Iraq had been a "gift" to Osama Bin Laden and al-Qaeda, by confirming the belief in large parts of the Muslim world that the US was an aggressive power.
After being gagged by the CIA, he decided to quit last week.
But he told me he placed the blame on a long-standing resistance from senior officers in the CIA and around the government to taking risks in going after Osama Bin Laden and not on the new director.
Whatever the cause of the current problems, there is a fear that a crisis in the CIA is the last thing needed at the moment.
"The agency seems in free-fall in Washington and that is a very, very bad omen in the middle of a war," said Congresswoman Jane Harman, the top Democrat on the House permanent select committee on intelligence, on CBS Television.
As well as Mr Scheuer, CIA deputy head John McLaughlin quit last week, and now deputy director for operations Stephen Kappes and his assistant Michael Sulick have also left.
What kind of agency emerges from the fallout - and whether it will be stronger and more effective - is something no-one yet knows.