Story highlights Trump has repeatedly questioned the purpose of America's continued involvement in Afghanistan

He also made contradictory statements about whether the war should have been fought

Washington (CNN) President Donald Trump will outline the United States' path forward in Afghanistan in a speech Monday night -- but he's been speaking out on the Afghanistan War for years.

Trump's address, scheduled for 9 p.m. ET Monday at Fort Myer in Arlington, Virginia, comes after Trump and Secretary of Defense James Mattis said a decision has been made on a new US strategy in Afghanistan.

Trump has often commented about the situation in Afghanistan, where the US led an invasion of the country in 2001 to topple the Taliban from power and eliminate a "safe haven" for al Qaeda. The war eventually became the United States' longest in history, and in 2014 President Barack Obama declared an end to combat operations.

But US support for the new Afghan government continued, and as of 2017 the Taliban remained a powerful force in the country. Gen. John Nicholson, commander of US forces in Afghanistan, said in February that the US and Afghanistan were at a stalemate with the Taliban.

Over the years, Trump repeatedly questioned the purpose of America's continued involvement in Afghanistan, but he also made contradictory statements about whether the war should have been fought in the first place.