Isaiah ch.31 - Bittachon. Faith in God

Isaiah advises Hezekiah to remain independent, and God will protect Israel: "Like a lion roars over its prey... like birds fly free." But can we simply rely on God and abandon human initiative? Is Isaiah's religious policy a reasonable one? In this article I quote: https://www.etzion.org.il/en/philosophy/great-thinkers/harav-aharon-lichtenstein/bittachon-trust-god