President Donald Trump's new defence secretary said that he may accelerate the withdrawal of US forces from Afghanistan and Iraq, to fulfill Mr Trump's pledge to end US involvement in foreign wars.
However, Christopher Miller also warned that the "war isn't over" against terror group Al Qaeda, indicating that by bringing service personnel home the US would not compromise long-standing military goals.
Mr Miller was appointed on an acting basis by Mr Trump on November 9, two days after the president lost his re-election bid, making him the fourth defence secretary appointed during his four-year term.
In a memo to the Defence Department workforce, Mr Miller said: "This is the critical phase in which we transition our efforts from a leadership to supporting role. We are not a people of perpetual war – it is the antithesis of everything for which we stand and for which our ancestors fought. All wars must end."
Mr Miller detailed in the memo his respect and admiration for the US military institutions and for the sacrifices made by the thousands of US troops sent to the Middle East since 9/11, but said that "many are weary of war – I'm one of them. Now, it's time to come home".
Mr Miller did not mention specific US deployments, but he did refer to Al Qaeda, saying: "this war isn't over. We are on the verge of defeating Al Qaeda ... we must avoid our past strategic error of failing to see the fight through to the finish," Mr Miller wrote.
Mr Trump had previously vowed to bring all US troops stationed in Afghanistan back home by Christmas.
Former defence secretary Mark Esper had reduced the US presence in Afghanistan by two thirds since the Trump administration signed a peace deal with the Taliban. However, Mr Esper said the US will maintain a presence of about 4,500 troops, until the Taliban followed through on their word to decrease acts of violence.