Is Japan a Vassal State of the United States? Starting with the Definition of “Vassal State”

The other day, I was watching a television discussion program when an interesting exchange took place.

The subject was the war in Ukraine and its relationship with Russia.

When one guest spoke about Russia turning Ukraine into a “vassal state,” the other objected.

“Russia is not demanding that much. It only wants to prevent Ukraine from joining NATO.”

The first guest responded:

“Forcing another country’s foreign policy to conform to your wishes, even through military force—that is precisely what it means to turn a country into a vassal state. We should use words correctly.”

The discussion became somewhat heated, but I largely agreed with this point.

Even without directly governing Ukraine, if Russia’s permission is required for decisions about foreign policy and security, Ukraine’s sovereignty as an independent state is restricted.

That made me wonder.

Is the frequently repeated claim that “Japan is a vassal state of the United States” actually correct?

What Is the Difference Between a Vassal State and Economic Dependence?

The term “vassal state” is used remarkably casually in political commentary.

If the Japanese government complies with an American demand, Japan is called an American vassal. If its economic dependence on China grows, it is called a Chinese vassal.

But economic dependence and control over a country as a state are not the same thing.

Suppose a country depends on one particular nation for most of its exports.

Ending that relationship would inflict severe damage on its economy.

But if it is willing to accept the loss, the option of ending the relationship remains.

The situation is entirely different if merely attempting to change its foreign policy results in a military invasion.

“Do not form an alliance with that country.”

“Do not accept foreign troops.”

“Do not change your security policy without our permission.”

If demands like these are enforced militarily, the country is independent in name only.

To me, the defining feature of turning a country into a vassal state is military coercion by another country when it attempts to choose its own course.

Is Japan, Then, a Vassal State of the United States?

Japan depends heavily on the United States for its security.

The economic relationship is also strong, and a deterioration in relations with the United States would cause serious losses.

But what would happen if the Japanese government announced the following?

“We will terminate the Japan-U.S. Security Treaty and ask U.S. forces stationed in Japan to withdraw.”

The United States would naturally object strongly.

It would probably apply diplomatic pressure, and the economic relationship might also suffer.

But would the U.S. military bomb Tokyo and try to force the Japanese government into submission?

I do not think so.

The Japan-U.S. Security Treaty itself contains a procedure for terminating the agreement.

In practice, ending the alliance would impose an enormous political and economic burden on Japan.

Even so, the option exists within the institutional framework.

Suffering losses if you leave and being prevented by force from leaving at all are completely different things.

If we ignore this difference and simply declare that Japan is an American vassal state, we lose the ability to distinguish that relationship from the kind of military coercion Russia is seeking to impose on Ukraine.

What Really Matters Is Whether You Can Defy the Other Country

Of course, the term “vassal state” has had a wide range of historical meanings and is not strictly defined only by whether military attack occurs. It can also include a situation in which another country effectively controls a state’s politics and foreign policy.

What I found important in this discussion, however, was the extent to which a country is permitted to make its own choices.

Following a great power’s wishes is different from being forced to follow them.

You may suffer economically if you reject the other country’s demands. But if you can still choose to reject them, some judgment remains in the hands of a sovereign state.

If an army invades the moment you refuse, however, the meaning of choice changes completely.

There is an obvious imbalance of power between Japan and the United States.

Even so, the treaty permits Japan to terminate the Japan-U.S. Security Treaty. Article X provides that the treaty ends one year after notice of termination is given.

By contrast, an attempt to change Ukraine’s foreign policy through military force is coercion directed at the country’s right to choose itself.

It is crude to dismiss both relationships with the same phrase, “vassal state.”

“Japan is a vassal state of the United States.”

Saying this can create the satisfying impression that you have seen through the hidden reality of international politics.

But the real question is not whether American influence is powerful.

What happens if Japan chooses a path different from the United States?

Shouting “vassal state” without asking that question takes the discussion nowhere.

The people who insist that Japan is an American vassal state remain free to criticize the United States every day. What a remarkably tolerant suzerain.