HO CHI MINH CITY, Vietnam – Poland will soon host production lines for South Korean tanks. Australia is buying warships from Japan. Canada will send uranium to India, while India offers cruise missiles to Vietnam, and Brazil builds military transport planes for the United Arab Emirates.

All of these deals were sealed in the past few weeks. Each one represents an attempt by middle powers to protect themselves as the conflict in Iran throttles global energy supplies, and as a high-stakes summit between US President Donald Trump and Chinese President Xi Jinping looms.

Global polls show the world has little trust in the US and China. Mr Trump and Mr Xi have both used their enormous leverage over trade and security to coerce or punish.

And in response, smaller nations are behaving as if they are stuck in the movies Godzilla or Dune – moving quietly in small groups, trying not to provoke the wrath of petulant giants.

“It’s fifty shades of hedging,” said Mr Richard Heydarian, a Filipino political scientist at Oxford University.

Or, as Dr Ja Ian Chong, a security analyst in Singapore put it: “No party wants to cross Beijing and now Washington, too.”

For countries watching from afar, dread and hope hover over the Trump-Xi meeting in Beijing, which is scheduled for this week.

In Asia, which has been hit hardest and fastest by oil shortages caused by the war and China’s tight control of oil-product exports, the mood is particularly grim.

Interviews with officials, and statements from leaders travelling the globe to secure trade and defence deals, suggest that most middle powers feel overwhelmed by the deteriorating world order.

Many believe the summit carries more potential for harm than help. And Mr Trum...