If you rely on someone else to run your capital markets, at best their crises become your crises. At worse they actively create crises either because that count

If you rely on someone else to run your capital markets, at best their crises become your crises. At worse they actively create crises either because that country sanctions you or because they're incentivised to under regulate (since they keep the profit but you suffer from the crash). Sanctions preventing Iran from working in USD or accessing Western banks have been 100 times more effective than sanctions on weapons or oil at bringing them to the negotiating table. That's why you don't want to rely on foreign Financial Services... There is tax revenue, jobs and the ability to sanction others. But it's the reliance on something you cannot control angle that makes this a MUST issue instead of a Would Be Nice issue.