In deciding to send another 1,400 Marine combat forces to Afghanistan to consolidate gains made during the troop buildup and put extra “pressure” on the insurgents, as Defense Department spokesman Col. Dave Lapan put it Thursday, President Obama is doubling down on his “surge” strategy. He is betting that more American fighters will inflict sufficient pain on the Taliban to prompt them to come to the negotiating table to make a deal, since clearly, America and its allies can’t kill or quell them all before Obama starts withdrawing his surge forces from the country.

But this is a risky bet which a growing number of even hawkish critics say is unlikely to work. The most recent among is Robert Blackwill, a tough-minded national security veteran of several Republican administrations. He warns in the new issue of Foreign Affairs that the United States and its allies are “not on course to defeating the Taliban militarily” and urges instead not more troops but what he calls “a shift to Plan B.”

The United States, he points out, now has 150,000 American-led International Security Assistance Force (ISAF) troops in Afghanistan. This, he notes, “is 30,000 more troops than the Soviet Union deployed in the 1980s, but less than half the number required to have some chance of pacifying the country, according to standard counterinsurgency doctrine.”

Adding 1,400 more Marines is not likely to change the calculus. Nor will “an occupying army largely ignorant of local history, tribal structures, languages, customs, politics, and values” be able to “win over large numbers of the Afghan Pashtuns, as counterinsurgency doctrine demands.” And it won’t make the Kabul government of Hamid Karzai less corrupt, more effective, or more credible, another indispensable ingredient of a successful counterinsurgency. "You are only as good as the government you are supporting," as David Kilcullen has observed.

What is Blackwill”s Plan B? Essentially, it’s a de facto partition of Afghanistan in which the United States would “stop talking about exit strategies and instead commit the United States to a long-term combat role in Afghanistan of 35,000-50,000 troops” to protect the non-Pashtun parts of the country. It acknowledges that the Taliban will “inevitably control most of the Pashtun south and east” and that “the price of forestalling that outcome is far too high for the United States to continue paying.”

In short, he argues President Obama should announce that the “United States and its Afghan and foreign partners will pursue a comprehensive counterterrorism strategy in Pashtun Afghanistan and a nation-building strategy in the rest of the country, committing to both policies for at least the next seven to ten years.” That is not likely to please foreign policy analysts who want the U.S. to withdraw from Afghanistan now. But such a de facto partition, he says, is the best we can hope for.

I haven’t visited Afghanistan for many years. I’m not sure whether analysts like Blackwill or Max Boot, who says the surge is working and urges us to stay the course, are right.

But I do have a sense that Americans are not being told what we need to know about this engagement and its underlying assumptions, length, and real goals. And speaking of counter-terrorism strategies, isn’t it time that the Obama administration acknowledge that we are engaged in a “war” on Islamic militants if not on their favorite tactic, terrorism, and put a price tag on that war so that Americans understand what we are being asked to pay for it?

The time for straight talk and more straightforward financial accountability about the cost of keeping Americans safe from another catastrophic terrorist attack is long overdue.

Judith Miller is a writer, Fox News contributor and Manhattan Institute Scholar.