[1] He studied at Harvard University's Kennedy School and obtained a master's degree in 1991.

[1] In 2006, he applied for the Liberal Democratic Party’s open recruitment for a by-election in Chiba’s 7th district for the House of Representatives.

delivered by LDP Secretary General Tsutomu Takebe and others gained significant attention, but Saito was defeated by a narrow margin of 955 votes by Kazumi Ota of the Democratic Party of Japan.

Saito was at the forefront of advancing a revised immigration law, which sought to overhaul the asylum process.

The revision was opposed by the CDP, which submitted a censure motion against Saito on 6 June 2023 in order to delay it.

Saito oversaw the expansion of Japan's semiconductor industry, through government subsidies to companies.