The fact that Iran's war has become a headache and a difficult dead end for Donald Trump is demonstrated by the continuous ups and downs of this past week. The United States has broken the ceasefire twice, and Iran has responded with skirmishes that both sides have described as "defensive actions". In parallel, a memorandum of understanding is circulating between Tehran and Washington that, for the moment, is not bearing fruit. The result is a climate of optimism and pessimism that shakes the price of oil, and which both Trump and Vice President J.D. Vance fuel with statements that often cancel each other out. Meanwhile, the Strait of Hormuz is tightening its grip on the global economy.