Is it permissible to buy authentic Arabian horses from Jews in Israel and sell them to them?

It is permissible to sell horses to belligerent disbelievers in this era because they are no longer considered a military asset or a source of power. This is because the general principle is the permissibility of trading in lawful goods with belligerents, with the exception of anything that strengthens them, such as weapons and the like, or anything explicitly forbidden by religious law. The proof for the permissibility of exporting to enemies, even during wartime, is that the Prophet, peace and blessings be upon him, permitted Thumamah ibn Uthal, may Allah be pleased with him, to export food to the people of Mecca despite the ongoing war between them.