If you could invest your money in only one of these areas, which would it be? And why?

1) defence
2) alternative energy sources
3) hi tech industries

number 2- that's our future and that seems to be what science is soo consciously working on these days- sometime sooon, those companys that discover and create alternatice eneergy sources will go huge.. that's my opinion though :D

Hi tech industries, the other 2 areas need hi tech items to continue to grow. Ideally I would diversify in all three.

i have to go with alternative energy == at least right now with every one from the the farmer to the the government putting money and time into this area it can only go up.

For the short to medium term (three months to a year), I would go with tech. Tech stock prices are generally low compared with earnings, sales and book value, so if I could invest in only one area, that would be it.
Alternative energy sources is an interesting area, but it's hard to know how it will shake out over the next few years. As a speculation, I might put a small percentage of my portfolio into the stocks of wind power and hydrogen fuel cell companies. Why not stick with conventional energy for now? By that, I mean refiners, oil service companies, exploration companies, etc. Oil demand is increasing as China and India develop, and the supply isn't getting any larger at present.

That would depend on what your objectives are - short, medium, long-term. Alternative Energy today is like biotech a few years ago. Lots of choices, and there will be many losers and a few winners. Defense is probably a steady one, but with the Democratic Congress, it would make me a little nervous. Technology, I still like IBM and think it is undervalued but over time. Global warming plays to a technology integrators strengths. Information technology will be a necessary component as we manage our use of energy. Recent article by T. Friedman of NYTimes lends itself to this thought.

Additionaly, tech has not participated in the market run-up over the past few years. It could be its time again.

Last is hi tech. The reason is that picking winners in a new technology is a gamble you will lose most of the time and the winners will face so much competition that it will not make up the difference.
Better is defense. But with the current political climate cutting their budget and likely to get much worse. No thanks, I'll wait for different politics.
Alternative energy sources is hot right now. Don't fight the tape. But you know the crash is coming in this area. You have no idea when. So be ready to dump when the time is right.

None. I'd invest in a diversified portfolio from all sectors. Good quality mutual funds are the way to go. Small cap, mid cap, and large cap. International and domestic.

DIVERSIFY!!!

I would say best and safest to invest in indexs and 10 year bonds.

1. Defense.
Defense is a proven play that consistently does well in good and bad economic times. Also, many defense contractors are diversified into other areas. Example: Boeing is a huge defense contractor, but also sells does lots of non military business.

Alternative energy sources is very overvalued. Look at how many companies are actually making money. Almost none. Look at how many are selling product. Few.

Like the early oil industry there were over 800 oil companies. In fifty years, there were less than 5. Figure alternative energy will be the same.

Hi-tech? Which? Alternative energy could be high tech. Biotech could be high tech. Computers could be high tech. Software could be high tech.

I think Biotechnology is in its infancy, and a lot of those companies are making real products and making money. Billions have been poured into basic research and we are just starting to see applications.

If you invest, you need some stocks that are speculative. These are your alternative energy.

You need some that are immediate need high profit companies. These would be oil.

And you need stocks that do well when everything else is down. Tobacco/defense/pharma

And retail when things are booming.

Good luck.

Alternative energy sources.1.For moral reasons, nobody needs to die for me to make a buck.2 both 1&3 needs me to function. We are running out of natural resources to produce power and if whatever alternative power we come up with will be a goal mine for investors.

Right now tech is on fire. Usually August is the time to start buying but because of the sub-prime concerns some big money has been floating into tech earlier this year. In the last couple of weeks some big gains have been made there but I believe there is still a lot more upside this season. Google, Intel and Hewlett Packard are my favorites to watch right now --also Cisco. Right now for tech all I've been holding onto has been Hewlett Packard for a variety of reasons (such as they are doing supposedly about 70 percent of their business internationally and with a weak dollar I like that. I believe that orders will be strong this quarter and their numbers (balance sheet, income statement etc) seemed really good to me right now.

I will also add that I'm really bullish on Google but the only downside was all the content lawsuits going on. Just something about it makes me not want to grab that even though I feel its still going to move on up.