What would the world look like if America was strict isolationist, and having withdrew all forces in the world, then what threats would it face?

 The world and the West overall sins away its day of grace, awaiting judgment, for the greatest enemy of most of the West and of world is the God of the Bible, who often has used the wicked as His sword of chastisement - Psalms 17:13. Thus surrender to God is the victory it needs.

Yet as regards the interim, since typical isolationist posters (who never seem to provide details as to their position) argue as if the US should not be involved in forming and supporting strategic allies against China and Iran, etc., then I asked perplexity.ai:

What would the world look like if America was strict isolationist, and having withdrew all forces in the world, then what threats would it face?

If the United States adopted strict isolationism and withdrew all military forces globally, the world would undergo profound geopolitical shifts, leading to increased instability, power vacuums, and emerging threats. Below is a comprehensive analysis based on current geopolitical assessments and expert projections.

Global Geopolitical Shifts

Power Vacuum and Rival Expansion

• Russia would likely expand its influence in Eastern Europe, testing NATO’s weakened defenses. Aggression against the Baltics, Ukraine, or Moldova could escalate, exploiting the absence of U.S. deterrence24.

• China would accelerate territorial claims in the South China Sea and Taiwan Strait, potentially invading Taiwan without U.S. counterbalance. Beijing might also expand economic coercion through initiatives like the Belt and Road56.

• Regional Powers (Iran, Turkey, North Korea):

  • Iran could dominate the Middle East, targeting Israel and Gulf states3.

  • North Korea might attempt unification with South Korea by force6.

  • Turkey could extend influence in the Mediterranean and Black Sea3.

Alliance Fragmentation

• NATO would weaken significantly without U.S. leadership, forcing Europe to develop autonomous defense capabilities. However, political divisions and military underinvestment could delay effective coordination24.

• New Blocs: Alliances like BRICS (Brazil, Russia, India, China, South Africa) might gain prominence, promoting alternatives to Western-led institutions5.

Threats to the United States

1. Economic Risks:

   • The U.S. dollar could lose its status as the global reserve currency, leading to financial instability. Trade routes might face disruption from piracy or regional conflicts, increasing costs for goods5.

2. Security Threats:

   • Direct Aggression: Adversaries like China or Russia could test U.S. resolve in the Pacific or Arctic6.

   • Nuclear Proliferation: Allies like Japan, South Korea, or Saudi Arabia might pursue nuclear weapons for self-defense, increasing global nuclear risks56.

   • Cyber and Asymmetric Warfare: State-sponsored cyberattacks (e.g., from China, Russia, Iran) would target U.S. infrastructure, with reduced capacity for retaliation67.

3. Loss of Global Influence:

   • International institutions (UN, IMF, WTO) could become dominated by China or Russia, eroding democratic norms and human rights standards5.

Regional Impact Summary (Hypothetical "Map")

Region	Key Changes	Primary Threats
Europe	Russian expansion into Baltic states; NATO fragmentation	Energy coercion, hybrid warfare, refugee crises24
East Asia	Chinese annexation of Taiwan; North Korean attacks on South Korea	Naval blockades, nuclear brinkmanship67
Middle East	Iranian dominance; ISIS resurgence; Israel-Gulf insecurity	Terrorism, oil supply disruptions35
Indo-Pacific	Chinese control of sea lanes; territorial disputes	Trade route instability, resource conflicts56
Global South	Economic collapse in aid-dependent nations; regional power struggles	Mass migration, authoritarian regimes5

Conclusion

A strictly isolationist U.S. would trigger a fragmented, multipolar world marked by heightened conflict, economic volatility, and diminished American security. Power vacuums would empower authoritarian states like China and Russia, while threats such as nuclear proliferation, cyber warfare, and disrupted trade would directly endanger U.S. interests. Without forward bases and alliances, America’s ability to project power or shape global norms would erode, potentially forcing costly re-engagement in the future. - https://www.perplexity.ai/search/

As stated 10 years ago,

Iran, China, Russia, and North Korea all play outsized roles in determining the future viability of the international order—from weakening the nonproliferation regime to establishing alternatives to the IMF and World Bank to violating international law. The next six years will be a critical juncture: Whether these “Big Four” choose to upend the international order, work within it, or create competitive arrangements will have lasting effects. - https://www.hoover.org/research/tomorrows-national-security-landscape