[When do we get liberated?]

It was called the Tripartite pact. Perhaps the only time Hitler abided by a treaty

[warsaw44]

Actually, Germany was in no way obligated to declare war on any country Japan was at war with. Nor was Japan obligated to declare war on countries Germany was fighting. The treaty was more of a mutual assistance agreement.

Numerous German generals were baffled by Hitler's declaration of war on the US. One wrote that they figured his grandchildren’s generation would be the ones that took out the United States.

[jamaksin]

On Tri-Partite ... it is important to note who attacks whom is the important thing.

US attacks Japanese would have triggered the Tri-Partite Treaty, not the other way around.

[SoCal Pubbie]

The relevant article of the Tripartite pact reads this way:

“Japan, Germany, and Italy agree to cooperate in their efforts on aforesaid lines. They further undertake to assist one another with all political, economic and military means if one of the Contracting Powers is attacked by a Power at present not involved in the European War or in the Japanese-Chinese conflict.”

Japan was not attacked. Hitler could have refused to declare war on the U.S. after Pearl Harbor, but chose to jump in anyway, ignoring not only his WWI experience of a two front war but taking on both the rest of Europe and the U.S. to boot.