A bunch of the assumptions - you need younger people to slave off to contribute taxes towards the retirement of the elderly - are a bit shaky to say the least.
The assumption that they will be able to supply that revenue is indeed shaky, but the assumption that one needs them to do so is well-founded. Traditionally immigration has been the safety valve for demographic mismatches, as ably documented here: http://www.ssab.gov/documents/immig_issue_brief_final_versio...
The assumption that they will be able to supply that revenue is indeed shaky, but the assumption that one needs them to do so is well-founded. Traditionally immigration has been the safety valve for demographic mismatches, as ably documented here: http://www.ssab.gov/documents/immig_issue_brief_final_versio...