"I think it's increasing every day, which means that we are in a race, really, we are in a race to be able to solve this problem", McMaster told an audience at the Reagan National Defense Forum in Simi Valley.
The latest missile flew higher than any others previously tested, before falling into Japanese waters. With every missile launch or nuclear test, Kim has improved his country's capabilities, McMaster said.
The piece - which came shortly after Kim Jong Un enjoyed a visit to a military tyre factory - added: "The US and South Korean puppet warmongers would be well advised to bear in mind that their DPRK-targeted military drill will be as foolish as an act precipitating their self-destruction". The other was the "testing of a long-range ICBM", the implication being this had been achieved with the most recent launch.
On Saturday Russia's Foreign Affairs Minister Sergei Lavrov reiterated his country's condemnation of the missile test.
North Korean monitoring group 38 North said the tremors could be an indication of "Tired Mountain Syndrome" - a condition where rock becomes increasingly permeable following a below-ground nuclear blast.
The tension in the Korean Peninsula is extremely high.
The statement came after Yonhap News reported that six US Raptor stealth fighters planes arrived in South Korea on Saturday for a joint air drill named "Vigilant Ace" scheduled for December 4 to 8.
"The facts above evidently show who is the real nuclear war maniac and the "nuclear demon" that disrupts and destroys peace of the Korean peninsula and the world", the statement added, the North's official news agency KCNA reported.
Vice Chairman Pak Kwang-Ho of the party's decision-making Central Committee told the crowd that, after Wednesday's test launch, "now no one can infringe our sovereignty and rights to survive and develop", according to the daily.
It's a risky world and as you look around and see there are a ton of hot spots, this next question is politically sensitive but you said everything was open when we started this thing, does an event like the indictment, foreign policy or national security impact, in other words, do foreign allies get rattled by it, do adversaries get rattled by it, does it somehow constrain the Trump administration foreign policy?.