( CNN ) -- This year `` will mark a turning point '' in Afghanistan and other regions , Defense Secretary Leon Panetta said Tuesday . In Afghanistan , `` our troops have been able to obviously reduce the levels of violence there . We 've seen the lowest levels of violence there in almost five years there now . They are successful in securing some of the key areas in Afghanistan , '' Panetta told reporters during a flight on his overseas trip . He 's visiting Djibouti , Iraq , Turkey and Libya as well as Afghanistan , where war still rages . He arrived Tuesday in Kabul and is meeting with Afghan President Hamid Karzai ; Ryan Crocker , U.S. ambassador to Afghanistan ; and Gen. John Allen , commander of NATO 's International Security Assistance Force . `` Obviously , there is greater success in the Afghan military and police . The Afghan military is engaging in operations , '' Panetta said . He said he thinks Afghanistan `` is on a much better track in terms of our ability to eventually transition to an Afghanistan that can eventually govern and secure itself . '' The issue of supply routes being cut off from Pakistan is expected to come up during Panetta 's trip . The United States is still sending supplies through the air from the north and south . Pakistan closed NATO supply lines in Afghanistan after a November 27 cross-border strike by NATO that killed 24 Pakistani soldiers . Panetta will meet with Afghan Defense Minister Abdul Rahim Wardak and will discuss the American commitment to Afghan security forces , a senior defense official told reporters before the trip . So , far , the official said , all indications and reporting back in the U.S. is that the supplies are still `` in pretty good shape . '' Supplies continue to flow in from the north and the stocks that they have on hand in Afghanistan `` are quite ample . '' `` This whole trip ( will ) give the secretary a chance to get a feeling for the situation on the ground , '' and the supply routes issue will be a topic of discussion , the official said . In an indication that the freeze on U.S.-Pakistani communications is thawing , Allen , the NATO commander , told reporters he recently talked to Pakistani Chief of Army Staff Gen. Ashfaq Parvez Kayani . Allen said Pakistan will soon send liaison officials back to NATO headquarters in Kabul . Panetta said the `` principal purpose '' of his journey is to visit U.S. troops and `` wish them happy holidays and a merry Christmas and happy new year . '' `` This is a difficult time for them to be away from their loved ones and it 's important that we go there and express my thanks , our thanks as a nation , for their service and for their sacrifice , '' he said . `` We 'll be touching a lot of key places that reflect some of the achievement that have been accomplished over these last 10 years as a result of the sacrifice and service of our men and women in uniform . '' He said he 'll participate in a ceremony marking the end of the U.S. combat mission in Iraq at the end of the year . `` This will be a historic moment where we basically enter a new chapter in Iraq , in which we will deal with them in a way that represents the kind of normal relationship we have with other countries in that part of the world , '' he said . He said the drawdown of bases and infrastructure has been a `` tremendous achievement . '' Panetta said Turkey is now a key ally , both in the Middle East and within NATO . `` They are extremely important to the ability to try to keep what 's happening in the Middle East heading in the right direction . They can have an influence on what happens in Egypt , in Iraq , in Iran , what happens in Syria . They have already taken a strong position to demand that Assad step down , '' he said , referring to embattled Syrian President Bashar al-Assad . `` To add to that the fact that they are willing to accept a defense radar system , I think it 's important for us to work closely with Turkey at this critical time because they can be an important ally and an important influence on the direction in the Middle East . '' Libya `` represents kind of the ultimate of what the Arab Spring should be about , '' Panetta said , using the term for the uprisings across North Africa and the Middle East this year . He said he 'll pay tribute to the Libyans and offer them support in developing a democracy . He said the NATO mission helped Libyans bring down Moammar Gadhafi 's regime , but now `` that country is headed back to the Libyan people . '' `` All is an indication that there are changes going on , '' Panetta said . `` This is a turning point that we 've all been a part of . But most of this is due to the sacrifice and commitment of our troops and the great work that they 've ( given ) over these last few years . ''
NEW : Defense Secretary Leon Panetta meeting with officials in Afghanistan . Panetta also will pass along holiday wishes to the troops . Turkey is a key ally in Mideast , Panetta says . Libya represents what the Arab Spring is all about , he says .