Senator Gillibrand also asked Dunford if he had met with transgender troops to address their concerns about the potential new policy.
"While the political space is clearly very charged right now, we haven't seen a change in the posture of North Korean forces and we watch that very closely", Marine General Joseph Dunford, chairman of the military's Joint Chiefs of Staff, told a Senate Armed Services Committee hearing for his reappointment.
"We haven't seen a change in the posture of North Korean forces".
Dunford said the USA should assume that North Korea has that capability and has the will to use it.
As far as Pyongyang's pursuit of a viable nuclear-tipped intercontinental ballistic missile capable of reaching US shores, Dunford said he agreed with US Strategic Command's assessment that North Korea would likely develop that capable by the end of 2018.
The US has also recently increased intelligence collection from North Korea, according to the army chief. With the October 15 deadline drawing near, President Trump has again ratcheted-up his criticism of the Islamic Republic and what he calls "the worst deal ever negotiated".
North Korea's top diplomat, Ri Yong Ho, argued Trump's tweet gives his nation the right to shoot down USA military aircraft, like the strategic bombers Washington flew close to the border between the two Koreas over the weekend.
Asia has been on tenterhooks as tensions soar, reaching new heights at the weekend when North Korea threatened to shoot down U.S. bombers carrying out missions close to its airspace.
"There are military options available to the president if our economic and diplomatic pressure campaign fails", Dunford said.
Dunford said the long-term, sustained presence was critical to demonstrating that the USA is committed to the region. That fight is now underway, and while the general cautioned against giving timelines, he said that combat operations in the city would likely be complete within the next six months.
"I would just probably say that I believe any individual who meets the physical and mental standards and is worldwide deployable and is now serving should be afforded the opportunity to continue to serve", Dunford told the Senate Armed Services Committee during a hearing to reconfirm him in his current job. "We may have to revisit that decision here on Capitol Hill", he said.
In particular, Dunford said, "we felt [an] ability to stop armored vehicles would be essential for them to protect themselves".
Before carrying out a preemptive attack against North Korea, the general said he would want to have the "full-throated support" of the American people, including Congress.
Several powerful Republican lawmakers - including Sens.