It is now more than 50 years since the dawn of the space age, and even today much of space activity remains the monopoly of governments and their sensitive defense establishments. Space exploration budgets are closely tied to defense and intelligence pursuits, and their budgets are all linked in some way, shape or form.

Indeed, it is correct to say that space activity is a niche human endeavor and not yet fully integrated into the mainstream of peaceful, sustainable, progressive human activities.

Commerce, the lifeblood of modern civilization and a chief agent of transformation, continually creates, evolves and sustains mainstream activities. Transportation infrastructures, housing, factories, and manufacturing and energy production and distribution are clearly mainstream activities.

The recent proliferation of Internet technology and associated business developments, which continue to spur its growth at a stunning pace in arenas as diverse as education, telemedicine and gaming, make it an ubiquitous and mainstream activity.

Energy production and distribution, with the petroleum industry playing a significant role, is a mainstream activity. While the media these days tends to highlight our addiction to fossil fuels and its effects on the biosphere, we rarely pay attention to the fact that petroleum by-product utilization, like polymer technology, have entered the mainstream and become an integral part of daily life for all of modern civilization.

Space exploration programs, both manned and robotic, are not mainstream activities. The allotted budgets for space exploration across the entire world simply pales in comparison to the resources oil companies bring to bear just for prospecting " exploring for new oil fields.

However, even while shackled to national security, space activity has managed to grow roots into modern society and continues to engage our noblest aspirations and uplift the human spirit.

A ringing success story of space entering the mainstream is telecommunications. Ten years after the birth of the space age, satellites were beaming TV pictures around the world and people were watching Neil Armstrong and Buzz Aldrin set foot on the Moon.

Twenty years later, geosynchronous communications networks made the world smaller by hooking up the financial and commerce hubs of the world and transporting data in ways and rates that terrestrial systems find hard to compete with, even in the age of the Internet and surplus dark fiber.

Space telecommunications is now a sturdy and lucrative industry, which is constantly evolving to meet the needs of the mainstream customer in the world of commerce and media while supporting the all-around needs of the defense establishment as well.

What are the other areas of mainstream human pursuits where space can play a significant role? The production of clean, environmentally friendly power from solar energy in space and its transmission and distribution globally could be a very lucrative industry.

Such a vision was first proposed in the 1960s, and after many iterations and reincarnations at various think tanks and conferences, it now again is becoming a strategic interest of both our nation and all the exponentially growing economies around the world.

Wireless transmission of energy, also known as power beaming, has inherent implications for environmental modification as well.

This nascent technology, which would allow us to control weather by design to ameliorate the effects of hurricanes and precipitation that cause deluges and droughts, could become a beneficial off-shoot of space-based energy production.

Power beaming, when trained outwards into space also could provide energy for spacecraft. Some concepts even propose using such beams to mitigate rogue asteroids that might endanger Earth.

Transportation is a vital infrastructure where the need is growing, ratcheting up the technologies for quicker access to the various metropolitan cities all over the world. Los Angeles, New York, London, Paris and Frankfurt now compete on equal footing with Shanghai, Dubai, Mumbai, Singapore and Tokyo. In this flat world model, quick and efficient worldwide transportation plays an even more crucial role. Transatmospheric vehicles, based on crafts like the space shuttle, could usher us into a new era in mainstream global transportation.

If space activity can do for energy production, power distribution (with potential for environment modification technologies) and transport infrastructure in the next three decades what it did for telecommunications in the last three, the ramifications for modern society are truly staggering.

Cheap and clean power in space and on Earth, and the ability to move goods and people swiftly around the world in a fraction of the time that it takes today, would make the world smaller and perhaps a much more tightly knit community.

The emerging private space companies, with little or no government support, are helping to mainstream space. Virgin Galactic and Burt Rutan's SpaceShip series are quite close to carrying people to the edge of space while ground support infrastructure is being created in parallel.

Bigelow Aerospace, with hard data trickling down from test articles in orbit now, is getting ready to commission its luxury hotels. Teaming with SpaceDev, Bigelow also is planning tourist missions to the lunar surface.

The Falcon series of launchers by Space Exploration Technologies Corp. will soon bring competitive pricing to the market. The X Prize Foundation, which successfully administered the first completely private suborbital spaceflight, now has teamed with Google Inc. to offer a prize for the first nongovernmental lunar surface mission. Other companies are working on spacesuits and related products and some have their eyes on the Moon, asteroids and beyond.

All these activities will contribute to a progressive and self-sustaining industry, catering to a wide range of economic interests. Just as the petroleum industry and the Internet now pervade every aspect of mainstream society, the space industry has the potential to transform modern civilization.

While many of us are wary of actions that might lead to an arms race in the orbital regime and weapons in space, the leaders of nations also know that space activity is the ultimate international arena for collaboration.

When commerce between nations grow, so do bonds, and history tells us that goodwill and peace dividends follow. There is no doubt in my mind that mainstream space activity holds the key for a peaceful and vibrant, pluralistic and multicultural modern civilization in this 21st century.

Madhu Thangavelu conducts the Graduate Space Concepts Studio in the Department of Astronautics and School of Architecture at University of Southern California, and is co-author of "The Moon: Resources, Future Development and Settlement."