MarketWatch reports Nvidia and Micron driving S&P 500 earnings growth, yet overlooks how this concentration stems from US export restrictions that have reshaped global semiconductor flows since 2022. Primary Commerce Department Bureau of Industry and Security rules, updated October 2023, curtailed advanced AI chip shipments to China, redirecting Nvidia's focus to domestic hyperscalers and inflating reported growth metrics. This pattern echoes earlier 2019 entity list additions, where secondary effects on Taiwan supply chains and European foundry capacity created temporary earnings spikes followed by volatility. Multiple perspectives emerge: one views the earnings boost as validation of AI demand resilience despite regulatory friction, while another highlights vulnerability if geopolitical escalation disrupts TSMC production or if enterprise AI adoption slows below current projections. S&P Dow Jones Indices data on constituent contributions confirms Nvidia's outsized role, but primary SEC filings reveal heavy reliance on a narrow customer base exposed to policy shifts. Synthesis of these elements shows the coverage understates how trade controls amplify market fragility rather than merely supporting growth.