Many GOP leaders are not only beginning to concede Nov. 4 to Barack Obama, they're predicting a landslide.
It leads to the question: Will John McCain put "Country First" and work to protect the GOP power to filibuster?
But another big issue is how the party is dividing along Cultural War lines.
Mr Frum argues that just as America is changing, so the Republican Party must adapt its economic message and find more to say about healthcare and the environment if it is to survive.
He said: "I don't know that there's a lot of realism in the Republican Party. We have an economic message that is largely irrelevant to most people.
"Cutting personal tax rates is not the answer to everything. The Bush years were largely prosperous but while national income was up the numbers for most individuals were not. Republicans find that a hard fact to process."
Other Republicans have jumped ship completely. Ken Adelman, a Pentagon adviser on the Iraq war, Matthew Dowd, who was Mr Bush's chief re-election strategist, and Scott McClellan, Mr Bush's former press secretary, have all endorsed Mr Obama.
But the real bile has been saved for those conservatives who have balked at the selection of Sarah Palin.
In addition to Mr Frum, who thinks her not ready to be president, Peggy Noonan, Ronald Reagan's greatest speechwriter and a columnist with the Wall Street Journal, condemned Mr McCain's running mate as a "symptom and expression of a new vulgarisation of American politics." Conservative columnist David Brooks called her a "fatal cancer to the Republican Party".
The backlash that ensued last week revealed the fault lines of the coming civil war.
Rush Limbaugh, the doyen of right wing talk radio hosts, denounced Noonan, Brooks and Frum. Neconservative writer Charles Krauthammer condemned "the rush of wet-fingered conservatives leaping to Barack Obama", while fellow columnist Tony Blankley said that instead of collaborating in heralding Mr Obama's arrival they should be fighting "in a struggle to the political death for the soul of the country".
During the primaries the Democratic Party was bitterly divided between Barack Obama's "latte liberals" and Hillary Clinton's heartland supporters, but now the same cultural division threatens to tear the Republican Party apart.
Jim Nuzzo, a White House aide to the first President Bush, dismissed Mrs Palin's critics as "cocktail party conservatives" who "give aid and comfort to the enemy".
He told The Sunday Telegraph: "There's going to be a bloodbath. A lot of people are going to be excommunicated. David Brooks and David Frum and Peggy Noonan are dead people in the Republican Party. The litmus test will be: where did you stand on Palin?"
I think traditional conservatives should tell the social conservatives: "Hey, you want the GOP? It's yours. See if you can win without us. We're going over here and starting a new party."
