Not really, isolationism was still relatively strong. It was Pearl Harbour that decisively turned it against the Axis. If Hitler either didn't ally with with the Japanese originally, or completely declared war on him he may have prevented American intervention. Considering that Japan was literally doing nothing for the German war effort, I don't see why it would be that insane. Obviously OTL Hitler was not that good of a strategist, but what if he was?
No isolation was dead by late 1941, 72% of Americans agreed that "the biggest job facing this country today is to help defeat the Nazi Government", and 70% thought that defeating Germany was more important than staying out of the war. Pearl Harbour hardened the perception that fighting the Axis was necessary to secure American security. The US government aren't going to fall for Hitler condemning the Japanese and the public wasn't buying German lies any longer.
In regards to Germany and Japan as allies, the Japanese presented a second front in a war against the United States and Britain. Germany knew that war with the US was inevitable and necessary, lend lease was helping to strangle the German war machine and they can't force the British or the USSR to terms if they keep receiving an endless supply of cheap war materials from America. Japan represented a front that would help distract the United States war machine and help cut Britain off from it's Australasian dominions and Asia, which mean't less men facing the Reich in North Africa.
There's no point poisoning relations with the only other country on earth (besides Italy) that is "on your side" so you can try and crudely trick the already galvanized United States (a nation you are effectively at war with already) that your nations aren't allies (despite publically creating an Alliance and attacking and enslaving conquered democratic nations). This idea doesn't require Hitler being a better strategist, it requires him to be a bigger idiot.
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