By Erica D. Borghard, Special to CNN

Editor’s note: Erica D. Borghard is the author of ‘Arms and Influence in Syria: The Pitfalls of Greater U.S. Involvement,’ published by the Cato Institute, and a PhD candidate in political science at Columbia University. The views expressed are her own.

The past few months have been difficult for the Syrian rebels as government forces, bolstered by Iranian support and Hezbollah fighters, have routed anti-Assad fighters around Damascus and Homs. However, recent reports suggest Syria’s rebels have successfully seized the key Minakh air base in Aleppo and are orchestrating a push to challenge Bashar al-Assad’s control of Latakia, a regime stronghold. If the rebels can consolidate these reported gains, it would certainly suggest a shift in momentum.

Yet the seesawing dynamic of the Syrian civil war suggests that these advances are likely to prove fleeting, and U.S. policymakers should not point to them as evidence that the Obama administration’s decision to arm the rebels represents sound policy. In fact, providing arms to the Syrian rebels is unlikely to decisively tip the scales to their advantage. As I argued in a recent Cato Institute paper, the United States is instead likely to be dragged into a more extensive involvement later – the very scenario advocates for intervention claim they are trying to avoid.

Waging war by proxy, whereby states provide nonstate groups with arms and other resources in exchange for fighting on the former’s behalf, is an attractive policy option for states when they are hesitant to use force directly. In this case, the Obama administration’s decision to arm the Syrian rebels is taking place in a broader context of American retrenchment and public wariness about extensive foreign interventions.

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Advocates of arming the Syrian rebels claim that U.S. policy objectives in Syria can be achieved at a relatively low cost without forcing the United States to commit to a large-scale intervention. However, the very aspects of proxy warfare that appeal to states – their covert, indirect and informal nature – also create the conditions for unwarranted commitment by states to conflicts.

First, the United States could become locked into a path of increasing involvement in the Syrian conflict through the institutional incentives that are present in covert operations. While the White House publicly announced on June 13 that the U.S. government was initiating a program of lethal support to the Syrian rebels, it was in fact already authorized under current covert operations law. Accordingly, the president can authorize covert action, provided he or she informs congressional intelligence committees, and is not required to make the nature of the operation known to the public.

What this means is that the specific parameters of the U.S. intervention in Syria remain vague and underspecified.

The secrecy surrounding aid to the Syrian rebels creates a real risk that the U.S. could get locked into even greater commitments in Syria later. Delegating authority for alliance management to bureaucrats, the CIA in the case of Syria, and providing them with a broad and ill-defined mandate to execute policies, impinges on political leaders’ abilities to use threats to influence the behavior of their nonstate allies. Specifically, proxies will not take threats to withhold or moderate support seriously if the political leaders making the threats cannot rein in the individuals responsible for executing them.

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Second, the United States could get trapped in an over-commitment in Syria through erroneous understandings of credibility and reputation. The fact is that despite claims by some policymakers, U.S. credibility is not at stake in Syria. The idea that Obama’s failure to adequately support the rebels would undermine the administration’s reputation for resolve in other arenas is misguided because Syria does not threaten core U.S. national security interests. Other states assess credibility based on a state’s power and interests in the issue at hand, on a case-by-case basis, rather than past behavior. Iran, for example, should not infer from Obama’s actions in Syria that the United States would not stand firm with regard to its nuclear program.

The rebels’ military vulnerability exacerbates these two problems. Their military deficiencies raise the question of what the United States should do if they are still unable to achieve and maintain pivotal military gains on the ground after receiving U.S. arms. As it becomes apparent that U.S.-backed rebels cannot complete the job, the United States will be tempted to escalate its involvement in the civil war to achieve its political objectives.

One thing should be clear: the United States should not have initiated a program to provide arms to the Syrian rebels. If our government is not careful, it will get sucked into an even deeper – and extremely costly – international commitment.