It Makes a Difference to the Sheep

Witness two competing interpretations of the resignation of Colin Powell. Lawrence Kaplan writes in The New Republic that Powell's departure signals the victory of the neo-cons:

With the departure of Colin Powell as Secretary of State, the Bush administration's great foreign policy rift has finally ended.
...
During Bush's second term, however, the president's foreign policy counselors will all be reading from the same page. Yesterday, after all, one side forfeited the argument.

Not so says the Heritage Foundation's Peter Brookes:

The rumormongers are wrong. Secretary of State Colin Powell didn't tender his resignation yesterday because Vice President Dick Cheney and Secretary of Defense Don Rumsfeld wouldn't play nicely in the foreign-policy sandbox.
Contrary to conventional wisdom, he also wasn't pushed out because he wasn't hawkish enough. Nor was he sacked because he was a moderate square peg in a neoconservative round hole.

Brookes goes on to list what he sees as Powell's accomplishments during his tenure as Secretary of State:

Secretary Powell can take a big chunk of credit for developing the international cooperation that has done so much to advance the War on Terror. Most terrorists are put out of business not by military action (in contrast to what you see on the evening news), but by international cooperation spearheaded by diplomacy, solid intelligence work and roll-up-your-shirt-sleeves law enforcement.

Powell has also advanced efforts to prevent the proliferation of weapons of mass destruction through such initiatives such as the Proliferation Security Initiative and disarming Libya of its WMDs. He also advanced American interests by explaining missile defense to skeptical members of the international community, which saw it as destabilizing.

And Powell played an important role in strengthening relations with such key allies as Japan, Britain and Australia, in developing ties with India and in putting contacts with China on a solid footing after a rollercoaster relationship during the Clinton years. He can also be credited with improving the morale at Foggy Bottom after it plummeted to record lows under Madeleine Albright.

This contrasts with Kaplan's assessment:

The wonder of it all is that Powell, for all of the battles he fought in the name of his "troops" at Foggy Bottom, accomplished next to nothing on their behalf. Iraq, Kyoto, ABM, direct negotiations with North Korea--nearly every time Powell waded into an inter-agency conflict, he lost. Even when he won, he lost. When, for example, Powell persuaded the president to dispatch a special envoy into the Israeli-Palestinian thicket, the result was an explosion of violence on both sides and the prompt collapse of the U.S. effort. When Powell convinced the president to return to the United Nations one last time before the invasion of Iraq in 2003, the effort backfired, doing nothing to budge the Europeans and much to discredit the cause of the Americans.

Which account is more accurate? Closer to the truth? Is there really a truth to get closer to? Given the ideologies and proclivities of both TNR and the Heritage Foundation, is the fact that Heritage praises Powell's achievements and doesn't see Powell's departure as a problem while the TNR finds Powell to be a failure whose absence will only make things worse surprising? Does anyone write without a set of ideological talking points these days?

More to the point: will either of these accounts/arguments convince a single doubter or detractor? If not, why write them?