When it comes to North Korea, all eyes are on nuclear weapons, but the lack of attention toward chemical and biological capabilities weakens defense against potential attacks, according to experts in the field.

After the breakdown of talks between the United States and Pyongyang last week, the future of not only nuclear weapons but biological and chemical weapons is uncertain.

“The real terrorists threats, primarily when you talk about weapons of mass destruction — nuclear, chemical and biological — are chemical weapons, biological diseases and radioactive materials,” said Paul Walker, vice chairman of the board of directors for the Arms Control Association.

Walker, who has worked in the international security field for more than 40 years, said chemical and biological agents are the biggest threats facing society today.

In the new Congress, lawmakers have paid particular attention to nuclear weapons. The House Armed Services Committee is holding a hearing on nuclear deterrence policies today and their counterparts on the Senate Armed Services Committee held a similar hearing on nukes last week. Neither panel plans to hold a hearing on chemical or biological weapons in the near future, according to committee staff members.

Jenifer Mackby, a senior fellow at the Federation for American Scientists, said that while the image of the mushroom cloud at Hiroshima and Nagasaki makes people fear the use of nuclear weapons, there is little public knowledge about biological weapons.