I smelled the air of Bangalore last week. It was foul. I remembered how in the late 1990s, when Delhi's air was dark and dirty, we had run an advertisement in the newspapers: "Roll down the window of your bullet-proof car, Mr Prime Minister, the security threat is not the gun, it is the air of Delhi." Since then, Delhi introduced compressed natural gas, it increased the number of buses, it got better quality fuel. With all this, the air got less dirty and less toxic. But now with each passing day, the city adds just below 1,000 new private vehicles. With each passing day, the gains of clean air are being lost. It is also losing the battle of the bulge: congestion is throttling the city; parking spaces are hard to find and pedestrians can't walk or cross roads without being run over.

Now Bangalore is similarly afflicted. I suspect we don't learn because we don't know how to do things differently. We live with the arrogance that we can tame the beast. Alternatively, we don't care. We don't roll down our windows. We don't smell the air.

Bangalore adds more vehicles than Delhi each day -- over 1,000. It has less road space than Delhi and more green space. The future the city has is ugly and hopefully not inevitable. The trees will have to make way for the roads and the flyovers that will carry its vehicles. But as the road space expands, as more flyovers get built, the expanding numbers of cars will inevitably fill it up.

The many-lane road that rings London -- its orbital -- is called the country's biggest car park because cars have filled it up. Closer home, the multiple flyover-cum-highway that has been inaugurated between Delhi and Gurgoan with the promise of a speedy ride home has already become a nightmare as cars crawl and people run madly to cross the road. We forget completely that stopping traffic at red lights also allows for people to cross. We forget because we don't walk. We drive.

The movers and shakers of Bangalore will tell you that their city is in transition. These are merely growing pains. Wait, till we have made our buildings higher, our streets broader, our many multi-level automated parking lots, our bridges, highways, tunnels, flyovers. Wait, till we have our city infrastructure in place. Then this problem of pollution and congestion will be a thing of the past. Just wait, don't worry.

This is an infantile illusion. The fact is that cities in the poorer world -- which lack investment to clean up technology or governance to get rid of old technology -- have not been able to deal with pollution. Take Beijing, where the organisers of the next Olympics have declared that the city's air is too unhealthy for athletes.

It is also clear that even the rich world, the world we wish to emulate, has only cosmetically dealt with air pollution -- and never been able to deal with congestion. New York is now spending US $350 million to implement the mayor's alternative plan to reduce its horrendous and crippling traffic congestion. This plan is primarily about spending money on buying new buses and building a rapid transit system for the city.

But Bangalore (like the rest of us) knows only how to follow, not how to lead. The fact is that today, the bulk of our city people travel by bus, by bicycle, or walk to work. The city has only 4,000 buses on the road and after much prodding is adding a few more hundreds. It is also building a metro rail, which will definitely help. But remember, till the metro gets operational -- the earliest date is 2010 -- the city would have added over a million vehicles to its already choked roads. And if people get wealthier, or if the cars get cheaper (as our industry is desperately trying to make them) then the vehicles added will be cars, not two-wheelers. This only means that vehicles will take more road space to carry even fewer people and will lead to worse congestion and even worse pollution.

Clearly, the option is to build a viable public mass transit system that will replace the car or marginalise it. At this moment, let us be clear, Bangalore like all our cities is on one road and it leads straight to hell.