There have been many suggestions as to what the United States should do regarding North Korea's development of nuclear weapons and the means to deliver them.
For example a recent piece by Denny Roy in the Huffington Post analyses six options for U.S. North Korea policy. In his words these are "let China do it; use military force; apply tougher economic sanctions; negotiate a freeze; accept North Korea into the club; and stay the course." As he says, all these options have significant drawbacks.
"Let China do it" means persuading China to increase pressure on North Korea to freeze its nuclear weapons program. Even if China had the wherewithal to accomplish this, pressure sufficient to make North Korea's leadership change its policy would also risk collapse of the North Korean regime.