Or HaChaim on Deuteronomy 25:17/אור החיים על דברים כ״ה:י״ז

1 זכור את אשר עשה לך עמלק, "Remember what Amalek did to you, etc." The reason the Torah singles out Amalek is because this nation was unique, attacking the Israelites by seeking them out, not even knowing where they were to be found. Just as an eagle flies far and wide to search for prey, so the Amalekites marched through hundreds of miles of desert in order to locate the Israelites.