A pair of U.S. Air Force F-15E Strike Eagles fly over northern Iraq after conducting airstrikes in Syria. (Matthew Bruch / U.S. Air Force)

Things are suddenly moving quickly as various allies start to commit to the American-led effort in Iraq and Syria. David Cameron was able to get a vote through parliament supporting combat operations in Iraq.  The Danes, Belgians and Dutch have all announced plans to send fighter planes to the conflict.  The Canadian government apparently asked the American government to produce a letter asking the Canadians to provide more help than just the 70 or so Canadian Special Operations Forces engaged in training in Iraq, and the cabinet will meet soon to discuss participating in the air campaign.

I cannot help but see many parallels with the Libyan air campaign.  As David Auerswald and I found in our book on NATO in Afghanistan, this all starts with one key reality: Countries have a variety of choices about not only what to send to the campaign but what those units will do once they get there.

After weeks of weighing its options, Britain's Parliament has voted overwhelmingly to approve airstrikes against Islamic State militants in Iraq. (Reuters)

When NATO members and partners became involved in the Libyan Civil War in 2011, they had many choices.  Some NATO countries stayed out of it entirely (Germany, Poland).  Some participated in the low-risk naval embargo (Bulgaria, Greece, Turkey, Romania) which actually required less change than opting out as most were already participating in NATO naval operations in the Mediterranean to counter terrorism.   Eight NATO countries and a few partners (Qatar, U.A.E) were willing to drop bombs on Libya.  Among those, there was another distinction.  Some would only strike targets that they had vetted before the planes left the ground.  A few were willing to send their planes to fly to a specific area and then be directed to targets of opportunity as they arose including mobile ones.

For the new effort against the Islamic State, there are many options that countries can choose.  We will probably only know the full menu after this campaign proceeds much further.  Right now, countries are starting to decide what to contribute.  The obvious choice is to provide fighter planes to facilitate air strikes — F-16s from many European countries, F-18s perhaps from Canada — mostly in packages of four to six planes (the Danes might be sending a spare since they are committing seven).   Some countries, such as Canada and Germany, have committed to training Kurdish forces and/or the Iraq military.  Nobody is committing to putting their own troops on the ground although it is never really clear what the Special Operations types are doing.  In Afghanistan, many countries deployed Special Operations units that operated outside of the limits imposed upon their regular forces.

The less obvious choice is much harder and more political — what to actually do?  So far, the pattern that seems to be emerging (but could easily change) is that the Arab partners — Saudi Arabia, Qatar, United Arab Emirates, Bahrain and Jordan — will strike Syria (although still don’t know which ones are actually dropping bombs and which ones are just flying into Syrian airspace as escorts), while the European partners (and probably Canada) will attack targets in Iraq.  The British vote was only on operations in Iraq, so do not expect British planes to join the bombing of targets in Syria.  Little of this is clear.  It can change especially where legislatures may opt to impose restrictions, but the pattern is suggestive.

For the Libyan operation, domestic coalitions developed in support of the effort.  Left-wing parties saw the war as a “Responsibility to Protect” effort, while right-wing parties saw it as part of supporting the United States and NATO.  The coalition politics of many countries will influence not just whether they send planes or trainers, but the rules under which they will operate.  Again, there is the shiny line between Syrian and Iraqi air space, but the decisions back home will shape whether particular countries’ planes will drop bombs only on fixed targets or on moving targets, that certain targets may be okay for some countries and not others, that countries will vary in how much expected collateral damage is acceptable and so on.  Every pilot has the power to say “no, I will not drop on this target right now” if they think that doing so is counter to the explicit or implicit instructions from back home.

Multinational coalitions always have these kinds of complexities, whether it is a NATO effort or not, which makes some people prefer unilateralism.  In this case, the gains from increased legitimacy, especially the Arab participation, are likely to greatly outweigh the inconvenience.  The European participation might also quell the complaints in the United States about free-riding and burden-sharing in NATO.  Those debates usually center on what countries are willing to pay, but as this campaign reminds us, it is the doing that matters most.

Steve Saideman is the Paterson Chair in International Affairs at Carleton University. He is the co-author of “NATO in Afghanistan: Fighting Together, Fighting Alone” with David Auerswald.