The new generation of terrorists in Syria is also thriving. Civil strife in the country has gradually evolved into sectarian warfare between Sunnite and Alawite groups. Many Jihad advocates in Jordan, Lebanon and Mauritania have called on Muslims to join the Syrian Jihad. Many jihadists from the Middle East, North Africa and even the West have joined the conflict in Syria, creating a new global "training center" for Jihad.

Drawdown ups threats

Since Barack Obama took power, the United States began playing down its global anti-terrorism activities. After the death of bin Laden, Washington released its new National Strategy for Counterterrorism, downgrading anti-terrorism in the list of its national security priorities. The Obama administration also shifted its focus of anti-terror from overseas back to the U.S. homeland, strengthening the domestic anti-terrorist systems while promoting the withdrawal of troops from Afghanistan. And in his second term, the Obama administration further deepened the contraction strategy on anti-terrorism. In a speech at the U.S. National Defense University, Obama put forward the goal of terminating the anti-terror war. He also increased the usage of drones and shifted command of the drone-strike program from the CIA to the U.S. military.

The huge cost of war is likely to be the major reason for the United States' shrinkage of its anti-terror strategy. As Al-Qaeda was heavily hit during the anti-terror wars, the United States also began to readjust its strategic focus to the Asia-Pacific. Though the Al-Qaeda headquarters in South Asia was battered, its branches and other regional terrorist forces continually expanded. International terrorist forces have sprung up individually. Therefore, the terrorist threat to the United States worldwide has not yet diminished.

Terrorist threats from the Middle East and African countries might continue to rise. The turmoil in the region has weakened the anti-terrorist efforts of various governments. For instance, after the downfall of Gaddafi, Libya has remained in chaos. The new government does not have the power and capability to take full control of the country. Tribal conflicts as well as terrorist activities remain rampant. Furthermore, Tunisia and Egypt are struggling with unstable domestic conditions in the two years since their previous regimes were toppled. The continuing partisan bickering in the two countries makes their political situation uncertain.

Regional security in South and Central Asia is likely to worsen. The U.S. troop withdrawal from Afghanistan will result in a huge security vacuum in the region. Terrorist forces including Al-Qaeda, the Haqqani network and the Islamic Movement of Uzbekistan could possibly stage a comeback for a variety of reasons. The weakness of the Afghan Army and other Central Asian countries means border control will be compromised in a volatile region without continued support from Washington.

Terrorist threats to the U.S. homeland are on the rise. Since Al-Qaeda is apparently no longer capable of launching large-scale attacks against the United States, it has instead called on its supporters to conduct individual attacks on U.S. targets. In addition, attacks launched by individual extremists (called "lone wolves") became another important type of terrorist threat to the U.S. homeland. Lone wolves act on their own without any outside command or direction. Therefore, their actions are more difficult to prevent, presenting an even more powerful psychological threat to the public.

In the past, terrorist forces were more easily suppressed, thanks to intensive anti-terrorism measures by the United States in Afghanistan, Pakistan as well as the U.S. support to the anti-terror efforts of Middle East and African strongmen Hosni Mubarak, Abdullah Saleh and Gaddafi. But now, with those regions mired in security vacuums, the United States once again faces major terrorist threats globally. The big challenge for the United States remains the question of how to preserve the current anti-terror achievements as well as deploy its resources to eliminate the remnants of Al-Qaeda and contain other emerging terrorist forces.

The author is an assistant research fellow with China Institutes of Contemporary International Relations

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