Army senior leaders on Monday again pushed for a service trained and ready to face an uncertain, volatile world.
Army Secretary John McHugh, who spoke to reporters alongside Milley, discussed the importance of ready and capable ground forces.
"If the last 18 to 20 months haven't proven the necessity of a viable land force, I'm not sure what will," he said. "All of us recognize the essential nature of a joint force. This has to be a joint force to provide multiple dilemmas to the enemy. We think we're an essential part of the very human nature of war as an endeavor."
Milley agreed, saying that history has shown that reliance on long-range weapons alone does not win wars.
"At the end of the day, the first and opening shots of any conflict are likely fired from the sea or the air, but the final shots are usually delivered on the ground," he said.
"We are a global power, and if we wish to continue to be a global power, we have to operate across a range of operations," he said. "We have to be ready to do that anywhere around the world any time."
One of the hot spots demanding the Army's attention today is Iraq. The Army has almost 3,000 soldiers there training and advising Iraqi troops.
When asked about the mission there, Milley said when the U.S. left Iraq in 2011, the Iraqi Security Forces "were not in bad shape."
In the years since, however, the Iraqi forces were not getting spare parts, their leadership was replaced, they didn't train, they didn't get paid, and their morale plummeted, Milley said.
After "three years of utter negligence," it wasn't difficult for the Islamic State to push into the country, he said.
However, Milley said he believes the Iraqis will fight if given the right tools.
"Having served in Iraq, my personal belief is yes, Iraqis have the will to fight," Milley said. "I believe with proper leadership, with good training, if you're properly resourced, then I think most peoples would have the will to fight for their own country."
The situation in Iraq is just another indicator of how unstable the world is, Milley said, adding that "the velocity of instability is increasing."
"The problems we've been most befuddled by are not the challenges we saw and planned for, it's the ones we didn't see," he said. "At some point, those two trend lines … are going to put this Army and this nation in a very dangerous place, and I don't know how to state it more frankly than that."
Michelle Tan is the editor of Army Times and Air Force Times. She has covered the military for Military Times since 2005, and has embedded with U.S. troops in Iraq, Afghanistan, Kuwait, Haiti, Gabon and the Horn of Africa.