I suggest that one of the dominant environmental issues in the West's future will be: How many people can live satisfied lives here? Population size is a factor of three variables: birth rates, death rates, and immigration. Birth, death and territory. Can any other issue cover such deep atavistic feelings? The issue will divide friends and even family, but it will not go away.


We know from the tragic pictures we see on our television screens that Africa holds the dismal record as the continent with the highest rate of annual population growth (2.93 percent). Less known is that the West has similar growth rates.


Nevada (3.9 percent), Idaho (3.1 percent), Colorado (2.9 percent), Utah and Arizona (2.7 percent), New Mexico (2.2 percent), and Montana (2.1 percent) make the West among the fastest-growing regions in the world.


California is growing at the same rate as India. When I moved to California in the 1950s, 10 million people were living there. Now the state's population is 32 million. The total is projected to double by the year 2040, as are the populations of the other Western states. Who benefits from this growth? Who pays?


Why does anybody want two people for every one now in the West, where we are already straining to accommodate growth?


Los Angeles has many problems: intolerable traffic, unhealthy smog, inadequate water, ethnic conflict. All have their genesis in population. Acid rain, climate change, loss of ozone, disappearance of species, loss of habitat - whatever the issue, at its root is population: too many people consuming too much in too little space.


Given present realities, why do we want our children to face an America of 400 million people?


It is axiomatic that infinite growth cannot take place in a finite world. We ignore this issue at great peril to our children. Population has its own momentum.


The first census in the United States, taken in 1790, found 4 million people. Since that time, America's population has doubled six times over, to 256 million. Two more doublings would give us 1 billion people - the same as China has today. Four doublings would give us almost as many people in the United States as now exist in the whole world!


Most environmentalists recognize high birth rates as a problem. Daniel Koshlad, editor of Science magazine, says we must inevitably "curb our primordial instinct to increase replication of our own species at the expense of others because the global ecology is threatened. So, ask not whether the bell tolls for the owl or the whale or the rhinoceros; it tolls for us."


If population is a problem, we must also inevitably deal with the painful issue of immigration.


Immigration presently accounts for approximately 40 percent of our population growth. Put another way, without immigration, the U.S. birthrate of two births per woman puts us on the road toward a stable population. With immigration, the relentless increase stretches endlessly into the future.


Immigration made sense when we were an empty continent in need of labor, but we are now a continent of 258 million people with 10 million unemployed and another 28 million discouraged workers outside the labor force. What public policy reasons today dictate bringing in approximately 1.5 million immigrants per year?


Many environmentalists feel awkward about raising the immigration issue because the United States consumes such a disproportionate share of the earth's resources. But as David Simcox writes, "Arriving here from less developed countries, grain and legume eaters become meat eaters, walkers or bus riders become car drivers, and users of one gallon of water daily consume 50 here."


The solution to American over-consumption is not to multiply that consumption by immigration, but to attack the problem directly. The environment is little helped by our guilt if we express it by allowing tens of millions of people to immigrate and become over-consuming Americans.


Let's raise the gas tax $1 per gallon, let's require recycling and reuse, and let's show America how over-consumption is irrevocably damaging the environment - but let's not compound our problem by more immigration in the name of guilt.


The poet Hillaire Belloc observed, "Truth, like roses, often comes with thorns." One truth the West must eventually understand is that its population cannot continue to grow forever. The West has a fragile ecosystem and humans are part of the ecosystem. We are not immune from the laws of nature - however clever our technologies. We must ultimately worry about carrying capacity, sustainability and how we affect our surrounding environment. We must worry about immigration.