Newcomers also increase flexibility, because they are unusually mobile both geographically and occupationally. This flexibility is ever more important as economies must change rapidly to stay in tune with changes worldwide. Immigration reduces the uncuttable social costs of the elderly. More and more of the U. S. and Israeli populations are retired people, with a smaller proportion of adults in the labor force. New immigrants typically are just entering the prime of their work lives and tax-paying years.
Immigration is the only feasible way to lighten the burden of the aging population.
Immigration also reduces the uncuttable social costs of defense. The taxes paid by olim contribute to the defense budget, which should be considered reductions in others' taxation because the total cost of defense increases very little with an increase in population. The same is true with reserve army duty. The capital-dilution effect is the main negative factor. If the number of farmers suddenly doubles, each farmer will have less use of the tractor, at least until someone buys or makes another tractor.