Islamic State (IS) again has proved its striking capability beyond Iraq and Syria. Recently, the so-called soldiers of the caliphate appear to have demonstrated chilling outreach, with terrorist attacks against Russia, Lebanon and France. The seemingly synchronised assaults that turned Paris into a war zone came just days after a bombing targeted a Shia district of Beirut controlled by Iran’s ally, Hezbollah, and a Russian passenger jet was downed over Egypt’s Sinai Peninsula. The rapid succession of strikes, all claimed by IS, suggested that a regional war is taking the shape of a global menace. The skill and determination of IS leaders and fighters, their organisational size and IS’ demonstrated lethality distinguish it from other terrorist groups. So, the potential global threat posed by IS will be different and very high in magnitude than the threat once posed by al Qaeda. But one huge irony is that even after the air campaign launched by the world’s super powers against IS, the terror group is still just as deadly and can carry out attacks thousands of miles away from its strongholds in the Middle East.Despite thousands of US airstrikes in Iraq and Syria that are reported to have killed about 10,000 IS fighters, the group continues to replenish its forces. Intelligence analysts have estimated that almost 30,000 foreign militants from more than 100 countries have entered Iraq and Syria since 2011, with IS gaining an average of about 1,000 fighters a month. A very important component is missing in this anti-IS strategy: the absence of any effective ground forces against IS. No amount of airstrikes can ever fully obliterate these hated Islamist fanatics because even very extensive air campaigns will still leave enough residual force, leadership and safe havens to allow IS the opportunity to reconstitute and reorganise itself. US forces have been bombing IS targets for more than a year without significant progress. Now, joined in those efforts is Russia but these countries have thus far been unable to seriously degrade the capability of the violent fanatics. It was argued that US air campaigns were aimed at ‘containing’ IS and stopping its expansion. But a strategy that only disrupts or contains without defeating or destroying the enemy has no prospect for any kind of successful outcome. IS is a serious enemy with significant skills when it comes to light infantry. Aerial bombing is a conventional modern counter-state strategy. It is the least efficient and least decisive strategy, even more so against IS in 2015 than against Germany in 1945. IS is not dependent on heavy industry or urban infrastructure, which if targeted by the bombing will affect its fighting capabilities. Air strikes alone are indecisive without a ground campaign to flush the terrorists/insurgents out of their hiding places and to contain them so as to separate them from ordinary civilians. There is a need for an integrated strategy, including an air campaign and commitment of ground troops. It has long been argued that local militias or groups that oppose IS can be used on the ground against the jihadist group. However, it is a hard fact that no group has the strength to take on IS in direct confrontation. Even Kurdish militias like the Kurdistan Workers’ Party (PKK) and People’s Protection Units (YPG), which faced battlefield success against IS in limited arenas, are unwilling to battle IS on a large scale and on multiple fronts. The Kurdish militias have a uni-focal approach towards safeguarding their strongholds from IS and consolidating their positions.To defeat IS and contain IS fighters, the ground campaign would need to be led by first-tier western armies, would need to be of a scale equivalent to the invasion of Iraq in 2003 and would need the cooperation of Iraq’s and Syria’s neighbours so that their borders can be closed otherwise IS fighters will escape to other states and territories. This cooperation will need to include not just western ‘allies’ — Kurds and Turkey — but at least tacit cooperation from western ‘enemies’ such as Syria, Iran and Russia. Without a western-led invasion, IS will dominate its current territory indefinitely in yet another lingering civil war, in yet another failed state with yet more contagion spilling over to other states. Consolidating its territory over years, if not decades, IS will use this consolidated territory as a launch pad for attacking western interests all across the region and even on a global scale. The writer is a columnist for the Middle-East and Af-Pak region and editor of the geo-political news agency ViewsAround. He can be reached at manishraiva@gmail.com