Complex sentence: Under such a scenario, the United States would have more leeway in using resources to combat the most pressing threats to its security and thus, the strategy of restraint would help preserve the country's prosperity and security more so than a hegemonic strategy.
Split into simpler sentences: Under such a scenario, the United States would have more leeway in using resources to combat the most pressing threats to its security. A strategy of restraint, therefore, would help preserve the country's prosperity and security more so than a hegemonic strategy.