In my student days, my dad asked me to prune a Buddleia in the garden. "Cut it right back" was the advice I'd been given, as that was apparently the right way to keep this plant in shape. I think I was more eager then as a gardener now, for I did indeed prune it right back - leaving barely half a metre of trunk left sticking out of the ground. The poor plant did not survive. But the memory of my gardening errors are perpetuated from time to time by my family.
In the 1960s, the "Beeching Axe" dramatically pruned Britain's railways. With hindsight, we see that this had a devastatting effect on our nation. Communities that relied upon the train for contact with the outside world were cut off, and some have dwindled to nothing. The loss-making branch lines suffered the clippers much more than the profitable main lines. It wasn't until a few years afterwards that people realised that the branch lines fed the main lines in the same way that leaves feed a tree. The promised increase in profitability of the main lines never happened, and passengers took to the roads instead.
Fifty years later, our roads creak under the weight of a traffic density they were never expected to carry, and more people travel by train than ever before. A few of those branch lines remained open. Some of them are now used by preserved railways (e.g. the Bluebell Railway). But the vast majority are unlikely ever to see trains along their routes again, because crucial parts of the track-bed were sold to property developers or were cut off by other infrastructure. Sadly, in most cases, the prospect of re-opening these branch lines to improve capacity on our railways is bleak.
Two branch lines exist near my home. There is a line from Watford Junction to St Albans Abbey, known as the Abbey Flyer. This line survived the pruning, and is relatively busy during the rush hour. At the Watford end, there are connections to Euston, Birmingham and to the London Overground. The route is single line all the way, which dictates a 45-minute gap between trains. I believe that this timetable is the main reason that it is poorly used: if a more frequent service were made available, I am certain that the success of this line would rise dramatically, challenging the main Thameslink service on the other side of town. To offer a more frequent service would require some practical changes, such as a passing-loop somewhere along the line, and these ideas are already under consideration.
The other branch line near my home is (or rather was) the onward line from St Albans to Hatfield. It was lost to the Beeching Axe. It is now a footpath and cycle path, known as the Alban Way. Since the line was removed in the 1960s, several short areas of this line have been developed which would make reinstatement of the line financially challenging. At least two housing estates now exist along the route. A road under-bridge has been modified so that cars go down less of a dip, and a short section near Hatfield has been lost to the development of the Galleria shopping centre and the A1M. Probably 95% of the line could be reinstated, but those last bits make it difficult to complete.
If it were possible to reinstate the Alban Way, then the East Coast Main Line (via Watford) would be re-connected to the West Coast Main Line (via Hatfield or Welwyn), via the Great Central line at St Albans along the way. All three routes are heavily used by commuters, and connecting them seems a beneficial thing to do. Routing the line past the Galleria might be seen as a challenge, or it might be a golden opportunity to shift shoppers from car to train. The issues of routing around housing estates and roads are more complex, but can also be surmounted. A fairly anonymous website describes some solutions to the problem, notably joining at the busier station at Welwyn instead.
This is just one branch line. There are of course thousands of others, and most will never see trains again. But there is hope. The tide appears to have turned, and Network Rail is actively re-opening some of those branch lines again. It's a small reversal of railway decline in this country, and changes such as these take time to implement, but it does appear that the tide has finally turned. It is like seeing fresh buds of a plant growing when you thought you'd killed it.