Micah Zenko, a fellow in the Center for Preventive Action at the Council on Foreign Relations, is the author of "Between Threats and War: U.S. Discrete Military Operations in the Post-Cold War World." He is on Twitter.

Any discussion about a U.S.-led military intervention into Syria's civil war should begin with the articulation of what the United States intends to achieve strategically. The Obama administration has offered a wide range of objectives, including strengthening the opposition and its defense capabilities, marginalizing extremists within it and compelling its various elements to unify and participate in negotiations with President Bashar al-Assad's regime. The administration says it wants to prevent the large-scale use or movement of chemical weapons, preserve state institutions, and, as President Obama stated in June, help to ensure a Syria "that is peaceful, non-sectarian, democratic, legitimate, tolerant."

An attack will aid the opposition, not just suppress the use of chemical weapons. So it will likely turn into a campaign to topple Assad.

What is unclear, based on information that administration officials have leaked to journalists, is which of these half-dozen objectives the White House believes can be accomplished with a limited, stand-off military force against military assets controlled by President Bashar al-Assad's regime. Based on early reporting, it appears that the only objective of the potential use of force would be to prevent the further use of chemical weapons by the Assad regime.

Therefore, the practical impact of the intervention would not be to protect civilians on the ground from state-directed violence, but to deter Assad from using one type of indiscriminate lethality, chemical weapons. If Obama decides that achieving this outcome is in the U.S. national interests - both in terms of Syria and any deterrent effect it has on the potential use of chemical weapons users elsewhere - then he will likely authorize the reported cruise missile and airstrikes.

However, it is highly unlikely that such an intervention can be so narrow that it will not force a deeper U.S. military engagement in Syria's civil war. Many have compared the potential upcoming use of force to the December 1998 United States and Great Britain attack against Iraq's suspected weapons of mass destruction and ballistic missile capabilities. In that four-day bombing campaign, only one-third of the targets were related to the production of weapons of mass destruction or ballistic missile programs. Similarly, in the case of Syria, most of what the United States bombs would not be directly tied to Assad's chemical weapon production, storage or weaponization facilities. Even a limited cruise missile strike will not be merely an attack on Assad’s chemical weapons capabilities, but an attack on the regime itself.

Subsequently, the United States will be correctly perceived by all sides as intervening on behalf of the armed opposition. From there, it is easy to conceive how the initial limited intervention for humanitarian purposes - like Libya in 2011 - turns into a joint campaign plan to assure that Assad is toppled.

If this is the strategic objective of America's intervention in Syria, President Obama should state it publicly, and provide a narrative of victory for how the United States, with a small number of partner countries, can and will achieve this.