The united states pursued an isolationist foreign policy for its first 150 years as a nation. for what reasons was this approach a reasonable one at the time ? the united states

 The United Stated needed to focus on it's political enforcement, increasing it's commercial alliances with the purpose of developing it's economy.

 The policy of non-intervention was reasonable because after the Independence war the United States was a developing country, so it needed to empower it's states, employing the money on the affairs of the nation.