An old man with thick glass in his spectacles sits at the side of the road in the early morning. His arms are raised as if in prayer, begging for rupees. It is a scene unchanged for thousands of years.

Alexander the Great might have glanced at a man like this as he led his conquering army so far into Asia before turning for home. But one thing has changed. Now the old man is sitting hopelessly on a motorway. Picked out in new concrete lettering high on the motorway embankment like a piece of Victorian morality is the single word: 'discipline'.

Pakistan's army on parade

But it has no effect, The giant, gaudily-painted trucks still thunder lethally past maybe a little faster than they used to, only just missing each other as their curtains of chains swing like skirts.

And a group of men sit across much of the road using the shade of a bridge over the motorway to protect them from the sun. Even now, this early in the morning, it is almost 30 degrees.

Altered landscape

South Asia does not change much, effortlessly absorbing the motorway into itself. But suddenly the whole landscape has been altered by India's explosions in the desert of Rajasthan, matched now by Pakistan's response.

Among the signs above the motorway, is one pointing to Srinagar - 305 KM. It is there not as a road-sign but an act of faith. You've not been able to drive to Srinagar for 50 years - the heart of the Kashmir valley is on the Indian side of the disputed border.

And tensions are rising on the border there again, now that India and Pakistan have joined the nuclear club.

Pakistan carried out its tests around Chagai about 500km from Islamabad

India's test should have been predicted - it was a manifesto commitment to the new Hindu supremacist government flexing its muscles.

But Pakistan's decision to respond is harder to explain. It is much smaller than India, so justifies its decision in terms of crucial nuclear security.

But the gains and losses were hard to juggle, and the tests were delayed by a week while the arguments were played out in the cool white corridors of power in Islamabad - Pakistan's capital city built from nothing, close to the Murree Hills.

The amount Pakistan stands to lose because of sanctions - $3bn, is the same amount that the country needs to service its debt. It is a huge, unaffordable loss.

And beyond the financial loss, Pakistan has a huge amount to lose in terms of international relations. Gone are the days when it was a trusted ally on the front line against the Soviet invaders of Afghanistan. But despite the end of that very close relationship, it has managed to keep good international relations.

For example, keeping off America's register of terrorist nations, despite clear evidence that Pakistan sponsored the separatist struggle against Indian control of Kashmir.

On the other side of the balance, what Pakistan had to gain by not testing would have included a substantial influx of so-called conventional weapons from America like F-16 fighter planes and the guarantee of protection from the American nuclear umbrella.

Pakistan turned all this down because it wants to stand on its own.

This is a proud country with prestige to gain from being the first Muslim nation to have the Bomb.

Going it alone

I burnt the soles of my feet walking in the midday sun across the white marble courtyard of the Faisal Mosque in Islamabad. I had surrendered my shoes at the entrance.

It is said to be the largest covered mosque in the world, although Saddam Hussein is, of course, now building a bigger one in Baghdad.

The preacher spoke fervently of the bomb as the Will of Allah. He said that Pakistan cannot stand beneath the wing of America any more, his words giving theological underpinning to going it alone.

And 20 minutes drive away across the new motorway in real Pakistan, the street markets of the ancient garrison town of Rawalpindi, away from the manufactured opulence of the capital, I found hardly a dissenting voice.

They want to go it alone too. It has made them strong. They are prepared to fight against India.

I remember an opinion poll five years ago which asked Pakistanis what made them feel proud of their Nation.

Imran Khan's cancer hospital came second on the list, but first was their possession, then undeclared, of the bomb.

I wonder if they will feel the same about the bomb once the economic sanctions really hit.