Known to residents as "Dear Leader," Kim Jong-Il has an iron grip on the mystery-shrouded, Communist spark plug of a country known as North Korea.

This enigmatic dictator most recently shoved his way into headlines by scoring a visit from former President Clinton by capturing two American journalists (note to self: cancel Pyongyang sightseeing trip). He has, however, been a constant news presence on the foreign affairs desk as he's led a nuclear arms program to try and bolster the country's ability to talk trash to larger nations.

So what does this have to do with investing? Well, having read up a bit on this quirky character, I think he has a number of lessons for us on what not to do when exercising supreme rule over our portfolios.

Killer confidence
You probably don't know this, but Kim Jong-Il is the best at everything he tries, and the man has done quite a lot.

He's flown fighter aircrafts, he's composed multiple operas, and he refers to himself as an "Internet expert." He also reportedly managed to shoot 38-under-par on his first golf outing and typically knocks in a few holes-in-one every time he hits the links.

While Kim Jong-Il can get away with these kinds of outlandish claims, an accurate assessment of your investing knowledge and skills is crucial. Just as there's very little chance the Dear Leader even sniffed par on his first golf outing, a beginning investor shouldn't expect to match the skills of Warren Buffett or George Soros from day one.

Investing as if you're more experienced or skilled than you really are can hurt you in many ways. For one, you may take on complex investments that require analysis above your skill level.

AIG, for example, tempted many investors as it went into complete free fall. But there's little that's quick or easy about understanding exactly how deep the bad derivative bets run or whether the company will ever be able to get out from under the government's thumb. Investors without the toolbox to understand these issues may now be sitting on big losses on AIG and have no idea whether they should hang on or sell to avoid more losses.

Many investors -- particularly single men -- have been bitten by overconfidence in the form of over-trading. Over-trading not only subjects you to hits from brokerage fees and taxes, but also can often lead to more misguided attempts at market timing and speculation.

You're correct if you agree with me
As might be expected for somebody as extraordinarily talented as Kim Jong-Il supposedly is, he has a zero-tolerance policy for dissention and rarely seeks outside advice when making important governing decisions.

But avoiding opinions that differ from your own can be investing suicide. There will inevitably be someone who thinks you're wrong, whether you're investing in the stalwart Berkshire Hathaway (NYSE:BRK-A) or the oft-debated Sirius XM (NASDAQ:SIRI). In fact, every time you buy or sell an investment, you're transacting with someone who holds the opposite opinion you do on that stock.

While you don't want to let contrary arguments scare you out of every investment idea you have, considering counterarguments can help you fully understand the risks you're taking on.

The trouble with isolation
If you want to get a pretty good sense for just how isolationist North Korea is, look it up on Google maps -- the entire country is whited out.

Having a persistently antagonistic attitude toward those outside the borders of North Korea has done no favors for the country. While taking a similar attitude toward your portfolio may not put you at risk of nuclear war, it can cause you to miss out on some of the best investing opportunities out there.

While many experts are predicting slow growth ahead for the U.S. economy, countries like China, India, and Brazil are likely set to slingshot out of this global recession and deliver some serious growth. A lot of great U.S.-based companies do a significant portion of their business overseas -- think 3M (NYSE:MMM) and Coca-Cola (NYSE:KO). However, you can get even more exposure to foreign markets by (surprisingly) investing in foreign companies. 

Canadian commodity favorite PotashCorp (NYSE:POT), for example, is a world leader in the supply of potash for crop fertilization. Brazil's Petrobras (NYSE:PBR) is one of the largest oil and gas players in the world, while China Mobile (NYSE:CHL) is the 800-pound gorilla in the world's largest market for cellular service.

Un-Jong-Il-izing your investing
I'm sure Kim Jong-Il is the world's greatest investor, but what I'm presuming would be his investing style runs counter to everything I think ours should be:

  1. Have an accurate assessment of yourself as an investor and avoid being overconfident.
  2. Consider the pros and cons of every investment and make sure to consider opinions that differ from your own.
  3. Banish "xenophobia" from your vocabulary and make the entire world your investing stomping ground.

If you'd like some guidance putting that last point into practice, consider our Motley Fool Global Gains investing service. Not only have I never caught advisors Tim Hanson and Nate Parmelee lying about their golf games, these two investing globe-trotters have managed to put together a portfolio of foreign-market investments that has outperformed both the S&P 500 and the MSCI EAFE indexes. You can check out exactly what they're recommending today with a 30-day free trial. Just click here to get started.

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Fool contributor Matt Koppenheffer owns shares of Berkshire Hathaway, Coca-Cola, and 3M, but does not own shares of any of the other companies mentioned. Berkshire Hathaway is a Motley Fool Stock Advisor pick. Berkshire Hathaway, Coca-Cola, and 3M are Inside Value selections. Coca-Cola and Petroleo Brasileiro are Income Investor picks. Google is a Rule Breakers choice. The Fool owns shares of Berkshire Hathaway. The Fool's disclosure policy actually shot 40-under-par its first time golfing, but it doesn't like to brag.