Are Nuclear Weapons Useful for Coercive Diplomacy?

The conventional wisdom in national security circles has been that in addition to their use as a deterrent, nuclear weapons can also be used as a tool of coercive diplomacy.  In other words, nations with nuclear weapons are able to achieve land, concessions or power that they otherwise would not be able to obtain without nuclear weapons.  A new book by Todd S. Sechser and Matthew Fuhrmann, Nuclear Weapons and Coercive Diplomacy, uses a careful historical and statistical approach to cast serious doubt on this conventional wisdom.  

Andrew Bast of the Los Angeles Review of Books summarizes the conclusions of the book:

In Nuclear Weapons and Coercive Diplomacy, scholars Todd S. Sechser and Matthew Fuhrmann want to answer the question, “What has [the United States] been able to do with nuclear weapons that it could not have done without them?” Sechser and Fuhrmann challenge the notion that nuclear-armed countries are more threatening on the world stage, that nukes help win negotiations, take territory, and generally bend the will of other states to their own. “An emerging wisdom in international relations scholarship,” they write, “says that countries with large nuclear arsenals can bully other states into submission.” Then they slowly dismantle that notion with a deep academic dive into a range of international conflicts over the last seven decades and conclude that “nuclear weapons have far less utility for coercive diplomacy than many people believe.”

Why is that? Sechser and Fuhrmann make a point that Trump would be wise to review in light of his comments about possibly battling ISIS with nukes. “The military utility of nuclear weapons is limited,” they write, “and often redundant to the capabilities of conventional weapons.” In addition, the international norms that have emerged over the last seven decades of the nuclear age dictate that any use of nuclear weapons would spark a fierce international backlash, one so powerful from other states and the broader public, they suggest, that would threaten the “security, prosperity, and the political fortunes” of any country and its leaders who actually launched the nuclear attack.

As the CATO Institute suggests, these conclusions raise significant issues:

 This has significant implications for U.S. foreign policy. What do these findings suggest we should expect from our nuclear-armed rivals, like Russia and China? Does it make sense to undertake preventive military action against nascent nuclear weapons programs in countries like North Korea? If Iran were to get nuclear weapons once the time-limited restrictions in the JCPOA expire (as critics of the deal suggest), how would that influence its behavior in the region?

Of course, the issue is far more complex that CATO suggests.  Iranian nuclear weapons, for example, would likely lead to other nations in the region (such as Saudi Arabia seeking their own nuclear weapons), which would destabilize the region.  Moreover, a country with otherwise weaker conventional forces can deter threats if they have nuclear weapons.  This, in turn, can allow them to engage in aggressive activity without threat of retaliation.  For example, would the US and its allies have come to Kuwait's defense if Iraq had nuclear weapons and threatened to use them?

What do you think?