we can jettison a boatload of risk by simply shifting from a domestic to a global portfolio
i suspect this is a gross oversimplification.* most all US individual investors live within country, and when investing domestically avoid a boatload
of risk that foreign investors assume when investing in the US.* this reduced risk should result in a portfolio more heavily weighted toward domestic issues.*
stated a bit differently, take two identical investements which differ only in that one is domestic, the other foreign.* the foreign investment is subject to currency risk while the domestic issue is not.* add to this additional risks reflecting relative policitcal stablility, legal protection, accounting standards and transparency, market efficiency etc. etc. etc. and the result would/should be an overweighting of domestic investments.