August 18, 2026, Updated Time: 03:45PM
US President Donald Trump’s approach to the Iran war is creating fresh tensions with two long-standing American partners — Oman and South Korea — as Washington pushes for greater pressure on Tehran and seeks to reopen the strategically vital Strait of Hormuz.
Trump’s latest statements and policy moves have raised questions about the direction of US foreign policy, particularly as his administration confronts stalled negotiations with Iran while simultaneously reassessing America’s military commitments to its traditional allies.
Trump Threatens Action Against Oman
Oman has historically played an important diplomatic role between Washington and Tehran. However, relations have come under pressure as negotiations aimed at ending the Iran conflict have failed to produce a wider agreement.
Trump said the United States could deal with Oman “very easily” if Muscat obstructed American efforts related to the Strait of Hormuz. His remarks followed reports that he had threatened military action if Oman interfered with US objectives.
The comments came as a 60-day US-Iran negotiation period expired without a broader peace agreement. The negotiations were intended to address the conflict and restore normal commercial shipping through the Strait of Hormuz, one of the world’s most important energy routes.
Why Oman Matters
Oman’s role is particularly sensitive because Muscat has traditionally maintained communication channels with both Iran and Western governments.
That diplomatic position has allowed Oman to act as an intermediary in difficult negotiations. Any major confrontation between Washington and Muscat could therefore complicate efforts to find a diplomatic solution to the Iran conflict.
The Strait of Hormuz is also crucial to global energy markets. Prolonged disruption to shipping through the waterway could keep oil prices elevated and increase pressure on economies that depend heavily on imported energy.
South Korea Also Faces Pressure
Trump’s tensions with allies are not limited to the Middle East.
The US president has ordered the Pentagon to scale back joint military exercises with South Korea, citing the cost of the exercises and Seoul’s reluctance to support the US position on the Iran conflict.
The decision affects the long-standing US-South Korea security partnership, which is primarily designed to deter North Korea.
The latest military exercises continued, involving thousands of South Korean troops, but Trump’s call for a reduction has generated concern among security officials and analysts who view the drills as an important component of regional deterrence.
Trump Points to Relationship With Kim Jong Un
Trump has also highlighted his relationship with North Korean leader Kim Jong Un while discussing the future of US-South Korea military exercises.
According to reports, Trump said Kim had responded positively to US outreach after Washington announced changes to the military drills.
The development has added another layer of uncertainty for Seoul, which must balance its security relationship with Washington against the possibility of renewed diplomatic engagement between Trump and Pyongyang.
A More Transactional US Foreign Policy?
Trump’s latest moves have renewed debate over whether his administration is taking a more transactional approach to America’s international alliances.
Rather than treating military partnerships as fixed commitments, Trump has repeatedly focused on issues such as financial contributions, burden-sharing and whether allies support US strategic priorities.
His latest actions involving South Korea and Oman are being closely watched because both countries have traditionally been important partners for Washington. Critics argue that unpredictable pressure on allies could weaken confidence in US security commitments, while supporters say the approach forces partners to contribute more and align themselves with American objectives.
Iran War Remains the Central Issue
At the centre of these diplomatic tensions is the continuing conflict with Iran.
The 60-day negotiation window between Washington and Tehran expired without the wider agreement Trump had sought. The Strait of Hormuz remains a major concern because disruptions there can have immediate consequences for global oil markets.
Trump has maintained that Iran must not acquire a nuclear weapon and has shown little willingness to accept an agreement that does not meet Washington’s demands.
For markets and governments around the world, the biggest question now is whether diplomatic efforts can restart or whether the conflict will enter another period of escalation.
What Happens Next?
The coming days could prove critical for US-Iran diplomacy and regional stability.
Key developments to watch include:
- Whether Washington and Tehran resume negotiations.
- Whether Oman continues its role as a diplomatic intermediary.
- Whether commercial shipping through the Strait of Hormuz returns to normal.
- Whether oil prices rise further if the shipping disruption continues.
- How South Korea responds to the proposed reduction in military exercises.
- Whether Trump’s outreach to North Korea develops into direct negotiations.
- Whether other US allies reconsider their own security relationships with Washington.
The Bigger Picture
Trump’s latest moves show how the Iran conflict is affecting relationships far beyond the Middle East.
Pressure on Oman could complicate diplomacy with Iran, while changes to military cooperation with South Korea could reshape calculations in East Asia. At the same time, uncertainty around the Strait of Hormuz continues to create risks for global energy markets.
For the United States, the challenge is balancing military pressure on Iran with the need to maintain the confidence of long-standing allies.
For now, Trump’s foreign policy is entering another critical phase — one in which decisions made over Iran could have consequences stretching from the Persian Gulf to the Korean Peninsula.
Disclaimer: This article is intended for informational purposes and reflects publicly reported developments. The situation remains fluid, and details may change as governments issue new statements or take further action.
