NEW YORK ( TheStreet) -- The S&P 500 has been attempting to rally after U.S. growth data indicated that the economy expanded at a rate of 2.5% during the second quarter -- more than double the rate posted during the previous three months. This result was well above the 1.7% that was initially expected by the market consensus, and the positive news is being taken alongside the reduced possibility of military actions in Syria.With emerging markets in freefall and the potential reductions in Fed stimulus programs in the next few weeks, bullish investors have taken every available opportunity to capitalize on evidence of reduced uncertainty. VZ) and Vodafone ( VOD) have helped sentiment. Also, Guess? ( GES) saw single-session gains of more than 10% after its second-quarter earnings report showed a better-than-expected performance on the profit side. However, falling energy stocks are helping limit rallies because reduced concern over Syria conflicts has led to lower oil prices. GDP Not Enough to Sustain a Rally While the latest GDP figures are encouraging (and help support the Fed's view for growth into the latter part of the year), there is little reason to believe this data will be interpreted as positive enough to generate a sustainable rally. To be sure, the 2.5% GDP reading virtually ensures the Fed will have enough positive economic momentum to begin tapering its quantitative easing programs, but these reductions in stimulus will provide additional headwinds in equities for the next few months.