The Joint Comprehensive Plan of Action (JCPOA), also known as the Iran nuclear deal) is excellent; it is far better and more extensive than I ever expected (Don’t upset the balance of power in the Middle East, 23 June). If followed by all parties, it blocks all avenues for Iran to develop nuclear explosives. To be sure, it is vehemently opposed by Israel’s prime minister Netanyahu and Republicans in Congress.

I am a physicist who worked in nuclear safeguards and non-proliferation for 38 years at the Los Alamos national laboratory; the majority of my efforts were for and with the International Atomic Energy Agency (IAEA) that has the responsibility of inspecting the nuclear facilities of states signatory to the nuclear non-proliferation treaty (NPT). Among other things, I developed programmes that have been part of the initial IAEA inspectors’ training since 1980. I’ve trained many of the inspectors who inspect Iran today, and have inspected Iran’s facilities since it signed and ratified the NPT shortly after it came into force in 1970.

There are only three nations that have not signed the NPT: India, Israel, and Pakistan. All three have large nuclear arsenals and effective delivery capabilities. Israel has over 400 nuclear weapons of all types and the ability to deliver them anywhere in the world, including the US. Israel also has a policy known as the Samson Option that implies it will destroy the world if ever it feels in danger of falling.

Dr T Douglas Reilly

Los Alamos, New Mexico, USA

• Ali Akbar Salehi’s piece was a calm, reasoned argument for the JCPOA to be allowed to thrive, despite the expected noises from Trump and his ilk. Why is Iran so often seen as the enemy? The country is stable and calm and – much to the annoyance of its detractors – has regular elections that the Iranian people deem worthwhile participating in. Saudi Arabia, on the other hand…

David Gleeson

London

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