More than 1,000 Hawai'i Marines are serving in Afghanistan in what is likely to be a steady march of Käne-'ohe Bay Leathernecks to the country for years to come.

After meeting with a who's who of military and diplomatic experts on Afghanistan, retired four-star Army Gen. Barry McCaffrey, an adjunct professor of international affairs at West Point, recently provided a sobering synopsis of what those Marines — and the U.S. — can expect to face.

McCaffrey made the report at the invitation of Gens. David Petraeus and Stanley McChrystal, the top U.S. commanders for the Middle East and Afghanistan, respectively.

McCaffrey said we are unlikely to achieve our political and military goals in 18 months — the timeline set by President Obama for the beginning of a reduction in U.S. forces.

"This will inevitably become a three- to 10-year strategy to build a viable Afghan state with their own security forces that can allow us to withdraw," McCaffrey said. "It may well cost us an additional $300 billion, and we are likely to suffer thousands more U.S. casualties."

The Taliban believe they are winning, and the Afghan people do not know who will prevail — the central Afghan government or the Taliban, McCaffrey said.

Afghanistan is "still in the 14th century," he said. Seventy percent of the population is illiterate, and it is the world's second-most corrupt nation, after Somalia.

The $3.4 billion opium crop finances the Taliban, and corrupts police and civil authorities.

President Hamid Karzai is under enormous pressure from the U.S., his allies and the Afghan people, and is underweight, sick and has a nervous facial tic, McCaffrey said.

But Karzai also is brilliant, well-educated, nonviolent and a patriot who deeply cares for his people — even if he is imperfect and "has a collection of ruffians in his inner circle," McCaffrey's report states.

The retired general says the Afghan National Army is a growing success story, but the Afghan National Police are a work in progress, six years behind the army in development: "It will take a decade to create an Afghan National Police force with adequate integrity which can operate at village level in a competent manner."

The Afghan people are generally extremely grateful for the U.S. and international presence.

"However, the Afghans are extremely apprehensive that we will leave again, sinking them back to the chaos of endless civil war," McCaffrey wrote.

There is no "inevitability to history," he said, meaning the U.S. is not destined to fail like the British or Soviets. "We can achieve our strategic purpose with determined leadership and American treasure and blood," he said.