The start of the year has brought the withdrawal of US-led international troops from Afghanistan one step closer. This year will be pivotal, as it becomes ever more pressing to shore up the security situation in the Central Asian country and arrange the details of the transition that leads up to next year's withdrawal.

Afghan President Hamid Karzai is paying a visit to the United States this week, and he is scheduled to meet US President Barack Obama on Friday. They are expected to discuss how many US troops will stay in Afghanistan after 2014, which is a question of wide concern.

The Obama administration is committed to withdrawing the majority of its 68,000-strong military presence in the country. In fact, the administration gave the first explicit signal on Tuesday that it might leave no troops in Afghanistan after December 2014, which is a major departure from the Pentagon's view that thousands of troops may still be needed to deter al-Qaida and to strengthen Afghan forces. The Wall Street Journal reported on Friday that the Pentagon has prepared plans for a "residual" presence of up to 9,000 US troops in Afghanistan.