North Korea's missile launch "changed the game," national security expert says

North Korea's successful launch of an intercontinental ballistic missile has "changed the game," CBS News senior national security analyst Fran Townsend told "CBS This Morning" Wednesday.

Townsend's comments come as North Korean leader Kim Jong Un vowed Wednesday that his nation will "demonstrate its mettle to the U.S." 

"We knew they had medium- and short-range missiles which were much more of a regional threat. This now represents a direct threat to the United States. We're going have to do things differently. Sanctions alone have not worked and I think the timing of it allows the president now to put this at the top of his agenda in his G20 meetings," said Townsend, a former homeland security adviser to George W. Bush. 

Asked what can be done if sanctions alone are not the answer, Townsend replied, "During the Bush administration, we pushed quite hard to get our regional partners to pay more attention to this. China is going to have to really seriously implement. The reason we're hearing President Trump's unhappy is we know that 80 percent of the sort of supply chain into the program in North Korea comes through China still."

Townsend said China has yet to be incentivized to do just that and it's going to take the U.S. bringing something different to the table. 

U.S. calls for action after North Korean ICBM test

"China has always cared about the U.S. presence on the peninsula and so their great fear is an increased U.S. presence if the North Korean government falls. So instead of dancing around that issue, we're going to have to put that on the table while still reassuring our South Korean allies," Townsend said.  

Townsend pointed to the increased importance of our defensive tactics. 

"Diplomacy alone and diplomacy with sanctions alone has not worked. We ought to be honest with ourselves. I do think it underscores the importance of the THAAD--the missile defense we're putting in for South Korea," Townsend said. 

"I also think the thing we haven't talked about yet is the importance of our missile-intercept capability. And so it may be, the North Koreans ought to be prepared. The next time they do a missile launch, the United States might try to use its capability to intercept that."

However, the efficacy of that U.S. missile intercept system has been called into question.  

"I think what you're gonna see in Congress here in the United States is a real call to put further investment in that technology," Townsend said.