Future American operations present numerous risks.

The symbol: A few hours before the 13th-anniversary ceremonies of the Sept. 11, 2001 attacks, Barack Obama has not announced the end of the war against terrorism, as he would have liked to one day. He presented the American people with his strategy for fighting against the Islamic State in Iraq and Syria.

For the Democrat and Nobel Peace Prize winner, who hoped to leave a trace in history as the president who ended the Afghanistan and Iraq wars, this is a significant step. It results from the conclusion that if the jihadis of the Islamic State already represent a serious threat to the Middle East, they could soon strike the U.S.

Barack Obama has been pushing back the expiration date of the scaling operation. Pressed by the security experts in Washington, he finally accepted putting America back on a war footing, with the help of European and especially Arab allies to avoid giving the impression of leading a crusade against Islam.

For Barack Obama, whose rational and deliberate decision-making process is not always in line with the political tempo, choosing to intervene more massively does not respond to an ideology. We are not reliving a neo-conservative remake of March 2003. The previous American ambassador, Ivo Daalder, proclaims: “People may criticize him for being too cool, too calm, too collected at times. But those are great characteristics for a president confronting big security challenges.”

Future American operations, however, present numerous risks. In Syria, besides the danger of intervening in a civil war and playing the game of tyrant Bashar al-Assad, the U.S. Air Force will have a difficult time counting on ground support from a moderate opposition that won’t measure up against the Islamic State.

As for the American public, it will undoubtedly be necessary to prepare: The fight against jihadism could last for years, maybe even for a generation.