First, before we get to sex and human nature, let's get some necessary, but preliminary points out of the way:

It's not necessary for the physical makeup of the military to be representative of the population and a military career is not a "right."

How most other countries run their military should not determine how the U.S. runs its military - Let's suppose that you're a high school football coach, and you learn about some techniques or strategies used by the pros in the NFL. You may decide to adopt some of these into your own football program. On the other hand, if you're an NFL coach, and someone tells you about strategies used by his son's Pop Warner team, you might listen politely, but you'll probably disregard the advice. Similarly, leaders of the world's most powerful and effective fighting force, the U.S. military, don't need to listen to media activists recommending that we become a larger version of the Canadian military.

Morale and unit cohesion are pooh-poohed by the left, but have historically been a very important element in military success or failure - In athletics, professional coaches understand this, and those with a basic understanding of human nature and a general knowledge of military history should also understand the importance of morale and unit cohesion.

The military must hire and train with the understanding that the next war may have to be fought much differently than the last war - World War II was a different type of war from the Vietnam War (long guerrilla war), which was different from the first Gulf War, for example. At some point in the future, we may face another war similar in scope to World War II. Many rules and standards that seem to work in relatively short wars, where the U.S. faces a much weaker foe militarily, may cause problems in a different type of war.

Similarly, policies that can be made to work in a peacetime or a training environment may not work very well on the battlefield - Liberal journalists applaud mixed male-female units, but in a long-term, evenly fought, intense war, will the time, manpower, and money needed to enforce policies regarding sex, sexual harassment, and discrimination against women and mixed male-female units help or hurt our effectiveness?

Physical strength still matters - Some commentators have noted that a lot of military equipment can be operated by pushing buttons and that strength tests and the lowering of physical standards for women are unimportant. The problem is that in a war, especially a longer, more intense war, like World War II, soldiers may have to perform tasks that they were not originally trained to do. Versatility is a desirable characteristic in a soldier. Strength can also affect speed and endurance, which are crucial on the battlefield.

Men have several biological advantages over women - Men have greater physical strength on average; they're more physically aggressive (which is why over 90% of those in prison for violent crimes are men); and they don't get pregnant. Pregnancy is the main reason that the non-deployability rate for women is several times that of men. This is especially troubling, given the high level of specialization of some units.

Sex Changes Everything - OK, now we finally come to the main problem - human nature. A certain amount of sexual tension exists in an office environment, especially one filled with young adults of both sexes. However, workers are only together eight hours a day, five days a week, and most of the time, they're working alone, on their own tasks. Even in this environment, two lovers, especially if they aren't getting along, or if one of them is a manager, can be distracting, create problems for upper management, and reduce the productivity or effectiveness of an office. Multiply the sexual tension several-fold for a war overseas, where young soldiers are away from loved ones for long periods of time, 24 hours a day, seven days a week, working or even sleeping together as a team in a much more stressful environment.

Admittedly, this is less of a problem for peacetime troops, or in recent wars where we've had an overwhelming battlefield advantage, but we don't know what the future will bring - a protracted, more evenly matched, deadlier WWII type war will bring this problem to the forefront.  The intense male bonding of a "non-sexual" nature was crucial to unit cohesion, morale and effectiveness in many past wars.  Regarding sex, what's going to happen if a leader appears to show preferential treatment to his lover?  What if he has to pick a few soldiers for a dangerous mission - will his lover be included?  What happens to morale and cohesion if some soldiers are receiving love and sex on a regular basis and some are left out?  What if some soldiers are extremely jealous or show stalking tendencies?  What happens if  soldiers are willing to literally fight for their love interest?

Ultimately, the combat goal of the U.S. military should be to obtain the "best" group of people for the job, who will be able to operate under any potential set of circumstances in future.  The goal should not be to put together a bunch of "qualified" troops.  For example, when you hire someone to work for you, let's say a secretary, you interview candidates because you want the "best" person for the job, not just anyone who can type.  Even in liberal Hollywood, screen tests and auditions take place because the producer wants the "best" person for the job, not just anyone with a degree in acting or a certain amount of acting class hours.  This is something the affirmative-action crowd doesn't seem to understand.  The overly sensitive, politically-correct crowd has already caused U.S. troop deaths via changed rules of engagement, and they will push to further weaken our future military effectiveness, because conceptually, they can't understand the importance and the difference between "best" and "qualified."

Dan Nagasaki is the author of a book for teens and young adults: The Beginner's Guide To Conservative Politics.  Glenn Doi is a real estate broker in Los Angeles.