With the removal of US forces in the region, the countries of the Middle East may be able to solve their own issues in a way that is organic to their socio-political climate, without imperialistic interference from the United States. The wars in Iraq, Afghanistan, Syria, even Libya are all widely recognised and criticised as being illegal invasions or occupations and have arguably all had nothing but negative effects in the region. Arguably the US' Middle Eastern foreign policy has been more a strategy of creating a state of perpetual warfare to benefit no-one but the US military industrial complex, and the end of this could at least give some hope for diplomacy in the region.
Afghanistan is a losing war that history shows to be too difficult to solve through occupation, and with the Taliban having made territorial gains in recent years to be in control of three quarters of the country at present, it looks like America can do no better than the Soviets. Syria was arguably a US attempt to sponsor a regime change that ended in fuelling a weapons black market and unending violence, with Obama's secret authorisation of the CIA's 'Timber Sycamore' program being an effort to topple another adversary with less public criticism. Both have been disastrous operations and leaving may help these situations resolve through regional diplomacy, unquestionable something that cannot happen with the destabilising force of the US in the region.