New security threats are leading to renewed calls for U.S. military engagement . After Iraq and Afghanistan , Americans are wondering if the Pentagon can withstand any more . Withdrawal from these wars was supposedly a response to belt - tightening at the Pentagon . In addition to the trillions appropriated for war spending , the regular Pentagon budget grew by $ 1.3 trillion in constant dollars since 2001 to the highest levels in real terms since World War II . This time around , America is starting off in a much weaker financial position , says Bilmes .
New security threats are leading to renewed calls for U.S. military engagement . After Iraq and Afghanistan , Americans are wondering if the Pentagon can withstand any more . Withdrawal from these wars was supposedly a response to belt - tightening at the Pentagon . This time around , America is starting off in a much weaker financial position , says Bilmes .