In Book V of his Politics Aristotle writes that

Constitutions are preserved when their destroyers are at a distance, and sometimes also because they are near, for the fear of them makes the government keep in hand the constitution. 

Wherefore the ruler who has a care of the constitution should invent terrors, and bring distant dangers near, in order that the citizens may be on their guard, and, like sentinels in a night watch, never relax their attention. He should endeavor too by help of the laws to control the contentions and quarrels of the notables, and to prevent those who have not hitherto taken part in them from catching the spirit of contention. 

Some of this may seem jarring to us, as Aristotle is usually so calm and reasonable! Still, we should try and understand him.

First, by “constitution” Aristotle means something much more than the laws or political processes of a particular state. He refers more broadly how a particular order is “constituted,” in all its parts, i.e., its decision making, laws, culture, economics. One can think of their own familes as a kind of “constitution.” Parents make some “laws” that are explicit (perhaps, “no phones at the dinner table”), and there are some things that your family just “does not do.” You have ways of making decisions as a family that might vary, but would vary in a predictable fashion.

Let us suppose that mom and dad have a family meeting and declare together that “We are going to the beach this summer for vacation. You accept this as final even if perhaps you preferred to go elsewhere. You can now prepare to enjoy the beach as best you can. But what if dad says “beach” but mom says, “cabin in the mountains.” Their division would spark division amongst the children. Everyone would see the possibilities, and everyone would have an opinion. The uncertainty breeds division.

But division over where to go on vacation is relatively harmless. Imagine a different scenario with more at stake. Someone new moves into the neighborhood. He does live next door, but he is on your street several houses down. Some say that the new neighbor is a nicy guy, even if he is quirky and a bit mysterious. No one seems exactly sure what he does for work, of if he has a family. But he seems a bit lonely, so its important to reach out. Others say that he is a bad guy, mysterious for all the wrong reasons. He is someone to be avoided. But no one can say anything definitively.

Now imagine if your parents lacked clarity on how they viewed him. Sometimes they see him as a potential threat, sometimes they see him as a someone they should reach out to. They send mixed messages. They cannot decide. The kids too would be confused, and likely divided themselves. All kinds of theories would emerge in favor of every kind of approach.

This is the problem Aristotle alludes to. A threat far away is no problem. We have clarity on the situtation, and can relax. A threat close by also unites us, and again, it is the clarity that unites. A possible threat maybe in gray zone, maybe not, will pose a problem for the constituted order, even if they never actually attack. Their mere presence in the miasma of the in-between will breed internal division and disunion. Most “constitutions,” after all, are eroded from within rather than without.

It is the lack of clarity that divides internally.

In our own nation’s history we can think of some recent examples. Before we entered WW II, for example, the nation was seriously divided over whether or not we should involve ourselves in wars so far away, whether in Africa or Asia. Yes, the Nazi’s were bad, but how much did their “badness” impact us? After Pearl Harbor, we no longer had any doubts about the threat they posed, and we enetered the war entirely united.

This principle played itself out in our own living memory. After 9/11 as a nation we had clarity about our invasion of Afghanistan. We were attacked, and our attackers were there. We had our “Pearl Harbor” moment regarding Islamic terrorism. We invaded Afghanistan under a banner of national unity.

A few years later, we invaded Iraq with much less national unity and much less clarity. Was Iraq a threat? Well, maybe. Perhaps they had weapons of mass destruction, and perhaps Saddam Hussein would actively try to help those who wanted to harm us, but maybe not. We had no national agreement, but invaded anyway. The war lasted longer than we thought, cost more than we thought, and likely contributed to the financial collapse of 2008. One can argue that politically and culturally, we have not recovered from the fallout of these events.

Should we have invaded either country? The question is certainly important, but we can understand Aristotle’s point even better if we eliminate what we “should have” done from the equation. After all, the invasion done under the banner of unity did not have ultimate success (the Taliban is back in power), and the one conducted under national strife seems to have had some positive lasting effects (the constitution we helped install in 2005 still holds in Iraq). The question Aristotle wants us to consider is which conflict proved worse for our own constituted order, and here we have an obvious answer.

When we look at the Vietnam War, we again have a conflict almost guaranteed to cause internal division and threaten our constitution. We can see the violence and massive cultural changes in terms of family breakdown, the sexual revolution, drug culture, etc. as a byproduct of our involvement in a war in which we lacked clarity on the nature of the threat.

One the one hand, protecting South Vietnam could be seen as vital to our interests for many reasons:

• We had pledged to defend the country from communist agression. Whether or not we should have done this, once declared, we had to back up our words if we wanted our words honored in other places throughout the world.
• We had an interest in stopping the spread of communism, which was/is an evil ideology that wrecks great harm wherever it goes.
• South Vietnam’s coastal geographic position made it a key strategic point of all of Southeast Asia.

But the fall of South Vietnam could be seen as not a threat to us for equally valid reasons:

• Chinese and Soviet communism did pose a threat to us. But Vietnamese communism was more nationalistic, and thus, no real threat to the United States
• Furthermore, Vietnam had a history of conflict with China. It would be in our interest not to fight them but to court them as an ally against China.
• The perceived moral imbalance of a wealthy industrialized power attacking a poor peasant nation would never hold politically in the US, a country that mythologizes the underdog.

At the risk of oversimplifying a complex period in our history, our lack of clarity over a threat in the grey area led us into a labryinth that could only lead to the altering of our constittuted order.