By Ben Cope The truth is we simply don’t know how to boost birthrates in modern, liberal countries. But we do know that immigration can reverse demographic decline, says Ben Cope Britain is rapidly resembling a geriatric ward. The buildings are old and crumbly, the institutions even more so, and the people… well, they’re starting to get on a bit. The cause? Britain’s fertility rate has been below replacement levels – 2.1 children per woman – since the early 1970s and is continuing to fall (currently at 1.49). At this rate, the native population will soon peak and then atrophy. Britain will bec…