Facing Threats at Home and Abroad, Iran’s President Takes a Harder Line

Crises provoke unity as Hassan Rouhani’s defiant tone wins praise from military, conservatives

BEIRUT—For much of his presidency, Hassan Rouhani has been at loggerheads with Iran’s military and conservative establishment, as he forged diplomatic ties with the West to break his country’s international isolation.

But now with his political survival in question, Mr. Rouhani is sounding a lot like Iran’s hard-liners.

During a visit to...