He owns newspaper The Hokkaido Post.
Tadahito Kato started his professional career by working at Nippon Weapons, a state-owned weapon company controlled by the National Bank of Japan. He continued working at the company until shortly before it was handed over to the Japanese Imperial Army. Kato then got a high-paying job at Q3 company Nambu Arsenal, owned by Shinko Securities, where he received his Hard Worker Medal.
Soon after getting the medal, Kato resigned from Nambu and got a new job at Tequila Food owned by the Tequila Fitness Club. It is the first time he has ever worked at a food company. Later, he found a job at Q1 company Tirol Bakery of the Crystal Lotus Corporation shortly before ending up at the Aegis Weapons Manufacturing of the Japanese Defense Center, a government-linked organization. Now, Kato works at Nippon Gifts, a state-owned company.
On 3 January 2009, Kato founded the Yoshiyama Corporation in Kinki. As General Manager, he established the corporation's first subsidiary company, the Kuruwa Lottery shortly after. The company experienced limited commercial success because of the economic crisis Japan was facing at the time. The lottery company was eventually forced to shut down even before its first draw.
Kato joined The Bushido Party in late December and has since then published articles discussing political issues. On 17 January 2009, Kato officially declared his desire to run for congress. Along with his platform to call for a higher minimum wage and stronger diplomatic relations with foreign nations, he promised to donate 5 GOLD to the government treasury if elected.
His campaign was a success as he was elected without a wild card spot. He was the second most popular candidate in Hokkaido after experienced congress member Al Dente. Soon following election, Kato donated the 5 GOLD he promised to donate before the elections to the treasury.
On 14 February 2009, Kato was appointed Ambassador to Singapore by Secretary of State Origineel.NL. The next day, after the UBN party elections, he officially announced the creation of the Liberal Party of Japan and began serving as its first Party president.