There are a bunch of signs pointing to General James 'Mad Dog' Mattis as the next Defense Secretary

President-elect Donald Trump hasn't yet finalized his decision for who he'll tap to lead the Pentagon next year, but plenty of signs are pointing to retired Marine Gen. James Mattis as the top choice.

First and foremost among them are Trump's comments during an interview with New York Times reporters on Tuesday, in which he said he was "seriously considering" Mattis for Defense Secretary.

The comments came just a day after an off-the-record meeting the President-elect had with media executives and on-air personalities, in which he said "he believes it is time to have someone from the military as secretary of defense," according to Politico.

If Trump were to stick with that view, then that means the field of potential candidates has gotten much thinner.

There were a number of names initially floated, including retired Lt. Gen. Michael Flynn, Sen. Jeff Sessions (R-Ala.) and Sen. Jim Talent (R-Mo.). Both Flynn and Sessions have accepted other positions within the administration, while Talent is apparently still in the running, according to The Washington Post.

Trump met with Mattis on Saturday for about an hour to discuss the position. Not much is known about what they talked about, but Trump did ask the general about the use of waterboarding and was surprised that Mattis was against it.

Afterward, Trump tweeted that Mattis was "very impressive" and called him a "true General's General."

Besides receiving praise from Trump himself, Mattis has been receiving near-universal praise in national security circles and among some of the DC elite. Syndicated radio host Laura Ingraham, a Trump backer who spoke at the Republican Convention, said on Twitter that he was the "best candidate."

And Sen. John McCain (R-Ariz.), the chairman of the powerful Senate Armed Services Committee, offered a ringing endorsement of Mattis on Monday.

"General Mattis is one of the finest military officers of his generation and an extraordinary leader who inspires a rare and special admiration of his troops," McCain wrote in his statement. "I hope he has an opportunity to serve America again."

Mattis did have some competition from another retired general - Army. Gen. Jack Keane - who was apparently offered the job, but Keane declined it for personal reasons, according to NPR. When asked who Trump should choose instead, Keane gave two names: David Petraeus and James Mattis.

While both would seem a good fit for Defense Secretary, picking Petraeus would likely be a much harder one to get confirmed. Congress seems likely to grant Mattis a waiver of the requirement of a seven-year gap between military service and the civilian defense job, but Petraeus would bring plenty of baggage to a confirmation hearing. That would include a sex scandal and charges of sharing classified information, for which he received a $100,000 fine and two years of probation.

Mattis, 66, is something of a legendary figure in the US military. Looked at as a warrior among Marines and well-respected by members of other services, he's been at the forefront of a number of engagements.

The former four-star general retired in 2013 after leading Marines for 44 years. His last post was with US Central Command, the Tampa, Florida-based unified command tasked with operations in Iraq and Afghanistan, as well as more than two-dozen other countries.

He led his battalion of Marines in the assault during the first Gulf war in 1991 and commanded the task force charging into Afghanistan in 2001. In 2003, as a Major General, he once again took up the task of motivating his young Marines to go into battle, penning a must-read letter to his troops before they crossed the border into Iraq.

A number of defense secretaries who served under President Barack Obama have criticized him for his supposed "micromanagement." Even Mattis himself was reportedly forced into early retirement by the Obama administration due to his hawkish views on Iran, according to Tom Ricks at Foreign Policy.

Whoever is ultimately picked, the next head of the Pentagon will oversee roughly 3 million military and civilian personnel and face myriad challenges, from the ongoing fight against ISIS and China's moves in the South China Sea to the ongoing stress on the military imposed by sequestration.

The next defense secretary may also end up dealing with a nuclear-armed North Korea, and Russia is very likely to test limits in eastern Europe. The secretary will also need to reinvigorate a military plagued by low morale.

Mattis did not immediately respond to a request for comment from Business Insider.