Even more important is the presence of US and NATO bases, which are to be dismantled in mid-2016, according to current plans _ an undertaking that would take assets away from the fight.
Keeping the bases going would reaffirm Afghanistan's strategic importance to the United States. And though Ghani is likely to get a US commitment for funding, training and support for the Afghan military beyond 2016, his request to keep the bases open beyond that timeframe is still on the table, the European official said.
US military leaders in Afghanistan agree with Ghani that the US bases in Kabul, the southern city of Kandahar, the former capital for the Taliban's 1996-2001 regime, and the eastern city of Jalalabad should remain open ``as long as possible,'' the European official said. Germany was considering extending the life of its base in northern Mazar-i-Sharif, but the Italian base in the eastern city of Herat is not expected to remain.
In Washington, Ghani is also likely to raise the subject of a new, home-grown threat from an Islamic State affiliate. Though the offshoot's strength and reach in Afghanistan remain unclear so far, those who have swapped the white Taliban flag for the black flag of the Islamic State group, which is fighting in Iraq and Syria, are believed to have links to the group's leadership in the Middle East.
Both Ghani and his chief executive Abdullah Abdullah, who will accompany the president on his US visit along with around 65 Afghan officials, have referred to the Islamic State group in recent speeches. US Gen. John Campbell, commander of American and NATO forces in Afghanistan who speaks regularly with Ghani, told the Senate Armed Services Committee earlier this month that the rise of the group in Afghanistan was being taken ``very, very seriously.''
Ghani's government has imposed a gag order on local officials and police chiefs, instructing them not to discuss the IS presence with reporters, according to Mujib Khawatger of the free-speech advocacy group NAI.
What is known, is that the US military was behind a February drone strike that killed Abdul Raouf Khadim, a Taliban commander who switched allegiance to the Islamic State group and set up an IS recruiting network in southern Afghanistan. And Khadim's nephew and successor, Hafiz Wahidi, was killed with nine of his men in an Afghan military operation in Helmand on March 16, according to the Afghan Ministry of Defense.
Analysts say the extreme violence advocated by the Islamic State group is unlikely to appeal to most Afghans or even would-be militants, though a war-won share of the estimated $3 billion a year from Afghanistan's poppy crop _ a third of which goes to Taliban coffers _ could be appealing.
Parallel to his military struggle, Ghani is also trying to negotiate an end to the 13-year war with the Taliban and open a preliminary dialogue with those among the group's leadership willing to come to the negotiating table _ as a prelude to formal peace talks, possibly within two years.
Multiple efforts to start a peace process have failed in the past. For this, Ghani also needs US backing, to pressure the government in neighboring Pakistan, where many of the Taliban leaders are based, to bring the militants into the talks.
In the US, Ghani will also meet with donors, including the World Bank and the International Monetary Fund, in an effort to secure funds to alleviate Afghanistan's financial crisis and help his reform plans.
Exactly what he may come home with remains to be seen.
"Ghani is going with high expectations," said one of the officials close to the Afghan president.