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I. U.S. Domestic Political Polarization and Strategic Competition: The Dual Drivers of Power Centralization

In recent years, political polarization in the U.S. has intensified, with deepening ideological divisions between Democrats and Republicans, shrinking centrist space, and weakening congressional cooperation mechanisms. The new media ecosystem accelerates polarization, as social platforms amplify cognitive disparities and erode social consensus. Political polarization undermines governance efficacy, leading to policy reversals and the instrumentalization of major public policies for partisan mobilization, reducing governance stability. The electoral system has become highly politicized, with midterm election "flips" becoming routine, restricting policy continuity in the latter half of presidential terms. Political polarization and external strategic competition drive the centralization of federal power. Policy implementation bottlenecks and social fragmentation fuel demands for stronger state intervention, while strategic competition with China expands the concept of "national security." Both parties accept "illiberal" government interventions, legitimizing federal power centralization. Federal authority has broadened, with emergency mandates and executive orders bypassing legislative processes, blurring the division of powers between federal and state governments. State governments resist federal policies, weakening unified national governance. Institutional power concentration creates space for Trump’s personal power expansion, as political authority relies on charisma and mobilization capacity, eroding institutionalized party structures. Trump’s firm control over the Republican Party centralizes policymaking around his personal will, causing frequent foreign policy shifts. The GOP’s "Trumpification" trend intensifies. This power centralization and personalistic governance profoundly impact the stability and predictability of U.S. institutions and strategic behavior.

II. U.S. Domestic Politics and the Reshaping of China Policy: Continuity in Goals Amid Strategic Instability

Domestic political polarization and personalization of power lead to erratic and individualized China policy decisions. The Trump administration’s China policy lacked checks, with declining hawkish influence and unpredictability weaponized as a negotiation tool. U.S.-China trade friction oscillated frequently, lacking coherent strategic objectives. While escalating trade measures, the Trump administration’s goals were fragmented, with policy tools disconnected from broader aims. Nonetheless, Trump maintained continuity in core strategic objectives, prioritizing economic competition and framing China as a rival. Tech-war policies expanded, blending strategic persistence with tactical volatility. Amid broader U.S. foreign policy shifts, China’s relative urgency declined, with Trump favoring transactional trade-centric approaches over comprehensive competition.

III. The New U.S.-China Strategic Dynamic: Three-Dimensional Restructuring of Power, Policy Diffusion, and Political Drivers

Against shifting global dynamics and U.S. domestic polarization, U.S.-China competition exhibits new trends. U.S. motivations stem not only from systemic power shifts but also domestic political changes and leadership preferences. Bipartisan consensus frames China as a threat, hardening policies and narrowing reversal room. Congressional China policies grow assertive—e.g., tech export controls, land purchase bans. Trump’s personalized governance amplified decision volatility. While both Trump and Biden treat China as a strategic rival, their approaches differ: Biden emphasizes alliances and rules; Trump favors deglobalization and bilateral economic contests. U.S.-China competition now revolves around trade, tech, and geopolitics, reflecting Trump’s imprint. The rivalry is transforming across three dimensions: power interplay, policy diffusion, and political drivers. China’s structural balancing in strategic domains triggers U.S. concerns, shifting the paradigm from asymmetric interdependence toward symmetrical but decoupled relations. Anti-China narratives permeate subnational governments, forging cross-tier consensus. Polarization and populism weaken institutional checks, injecting leadership whims and electoral cycles into strategy, heightening unpredictability. Future competition will test not just hard power but governance resilience.

IV. From Institutional Leader to Transactional Power: The Logic of U.S. Retreat from Global Governance

The U.S. role in global governance is structurally transforming, shaped by polarization, nativist sentiment, and leadership ideology. Polarization drains support for multilateral commitments, as globalism loses electoral appeal. Governance decay and leadership turnover weaken institutional engagement. Trump’s unilateralism accelerated the rejection of multilateral frameworks (e.g., WTO, WHO, UN), retreating from rules-based order. This stems from globalization advocates’ decline and rising zero-sum nationalism. Globalist elites are marginalized, unable to form viable third parties or sustain influence. The GOP’s Christian nationalism and Democratic adjustments toward nativism reflect this shift. Once a globalization architect, the U.S. now views it as a vulnerability, adopting transactional unilateralism. Trump’s alliance skepticism undermines collective action, reframing partnerships as cost-sharing tools. The U.S. transitions from system-builder to selective participant—or saboteur—prioritizing short-term interests over institutional stewardship. This reflects deep societal and electoral shifts unlikely to reverse soon.

V. Conclusion

U.S. domestic upheavals are reshaping foreign strategy, notably toward China and global governance. Polarization, social fractures, governance erosion, and power concentration heighten unpredictability and conflict risks. In U.S.-China competition, bipartisan consensus coexists with tactical volatility. Trump’s personalized, transactional approach lacked strategic coherence. The U.S. shift from multilateral leader to selective participant complicates China’s external environment. Future rivalry will test governance resilience. U.S. political trends will keep fueling strategic instability, deepening bilateral complexities.

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