"Instability plus lack of time make it almost impossible to lay the necessary groundwork for one of the most important foreign policy summits in the history of this administration."

Assuming there is a verification process agreed to that will ensure North Korean compliance, the United States and its allies will have to consider what steps they will be prepared to take in return: force structure reductions, economic aid, issues related to a permanent peace agreement with North Korea.

The ability to seriously evaluate each of these and other related provisions in the next few weeks and do it with the approval and support of our allies is near impossible.

It is no secret that this president has little diplomatic knowledge or experience nor does he have the patience to devote the time necessary to fully prepare for a high level summit. Without a comprehensive and well thought out strategy working closely with our allies, this president is likely to walk into a summit believing that the strength of his personality alone plus his gut instincts will be enough to prevail. That is a recipe for disaster.

Added to this is the large turnover of key personnel in critical national security positions, some of whom will have to go through a time consuming nomination process in the Senate. Under a more stable White House, it would be difficult enough to fully prepare for that kind of high level meeting. Instability plus lack of time make it almost impossible to lay the necessary groundwork for one of the most important foreign policy summits in the history of this administration.

The reality is that the president has two choices to avoid disaster: 1) assume that the summit will largely be a photo op with Kim Jong Un, with an agreement on a broad framework of issues to be considered in future negotiations, and a decision on a place and time for an agreed set of negotiators to begin discussion on the specifics of a possible agreement; or 2) postpone any summit until designated negotiators have determined that there is in fact a set of elements and conditions that can be agreed to that will result in the denuclearization of North Korea.

There is no question that the present circumstances do provide an important opportunity to negotiate a potential agreement with North Korea. The president indeed deserves some of the credit for bringing about this situation due to the increase in sanctions and his relationship with President Xi. But to be successful, it will take time, serious preparation, careful planning and extensive consultation with our allies. Tweeting will not do it!

Commentary by Leon E. Panetta, former Secretary of Defense and Director of the CIA under President Obama and former Chief of Staff for President Bill Clinton.

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