TWO snapshots from the tumultuous first Bush term illustrate why Colin Powell’s tenure as America’s top diplomat was always likely to end, if not in tears, then in bitter disappointment.

In May 2002 Dick Cheney was discussing Iran and how the US Administration should treat its ruling theocrats and its elected reformers. “Are they two sides of the same government or two separate governments?” the Vice-President asked, adding: “The same question applies to Don Rumsfeld and Colin Powell.”

Later, as the White House made its case for war in Iraq, General Powell considered the political forces ranged against him across the Potomac River in the Pentagon — Mr Rumsfeld and his neoconservative cohorts Paul Wolfowitz and Doug Feith.

“It was a separate government out there,” he mused. From the outset neither side believed they were on the same team. And both sides could not win. The running battles, caricatured as Washington’s lone dove struggling against the forces of darkness, came to define the Administration as well as acting as a debilitating drag on its energies.

But President Bush never lifted a finger to force a truce. Quite the opposite, he portrayed the to-and-fro as the sign of healthy dialogue. He said he wanted vigorous debate, though it slipped repeatedly into vicious invective. It was a recipe for suspicion and confusion, constant mistrust and occasional chaos.

General Powell grew to personify the divide, largely because he was often on the receiving end. Earmarked by Mr Bush to burnish his 2000 election credentials as a compassionate conservative, Powell fans saw a pattern in which their man was used and abused.

Early in 2001 General Powell was asked if the new Administration intended to pick up its North Korea policy and missile talks from where the Clinton team left off. Yes, he said.

The following day Mr Bush, who at the time was defining himself as everything that Mr Clinton was not, publicly humiliated his chief diplomat by announcing he was junking his predecessor’s policy of dialogue with Pyongyang. General Powell loyally took the hit. “Sometimes you get a little too far forward on your skis,” he explained diplomatically.

It was a position with which he grew familiar. A Middle East peace conference he had championed and announced was downgraded by the White House to an informal meeting.

After lecturing Israel against what he termed “targeted killing”, General Powell was forced to listen to Mr Cheney talk of “legitimate defence”.

While visiting Ramallah, General Powell was ruthlessly undermined by Mr Rumsfeld back in Washington. One reason he undertook fewer foreign trips than his predecessors was concern that he would fall victim to scheming in his absence.

General Powell did enjoy some successes. He and Tony Blair persuaded Mr Bush to confront Iraq via the United Nations. He, again with Mr Blair, won Mr Bush’s support for Europe to negotiate with Iran over its nuclear capability — an approach which may be bearing fruit.

But for all the infighting, the most vivid image of his tenure was when Washington’s warring factions were for once all on the same side.

When General Powell held up a small vial of white powder before the UN Security Council in early 2003, lending his considerable authority to Mr Bush’s case for war, he did his boss his greatest favour.

He could see that much of the CIA’s “evidence” of Saddam Hussein’s weapons of mass destruction was flimsy. He did not realise, though, that the whole case was as fake as the “anthrax” he waved.

No one, however, spends 30 years in the US military without knowing how to respond to an order. Whether he subjugated his judgment to salute his commander-in-chief, only he knows.

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