I don't know that it ends very well for Japan. At the time, the United States has 5 sea-going battleships in commission (Iowa, Kearsarge, Kentucky, Alabama. Illinois), plus the three Iowa class coastal battleships already in commission. They have the Wisconsin commissioning in 1901 and the three Maine-class battleships launching in 1901 and likely able to commission by 1902 in wartime conditions. There's also a number of relatively heavy protected cruisers like Olympia and New York that fought the Philippines battles of the Spanish American War just two years prior--a navy of trained professionals just a year or two off their latest major war, who have had time to absorb the lessons of it without forgetting them.
By contrast, the Imperial Japanese Navy has just 4 battleships (Fuji, Yashima, Asashi. Shikishima) with Hatsuse completed and due for delivery from the UK in early 1901. The last is important to note: Japan was for the most part unable to build their own capital ships at this time, they were buying them from the UK. Any ships added to the fleet after the war, like Hatsuse, would need to run the gauntlet to the Med and then through Suez to reach home waters, risking interception along the way (and that even assuming the US doesn't apply pressure to avoid the ships being delivered--perhaps, in the ultimate irony, purchasing them instead by outbidding Japan).
At the start of the war, the US is fighting an active and somewhat brutal campaign to subjugate the Philippines, which the Japanese may be able to intervene in if they can drive off the US Asiatic Squadron. The Japanese required US financial support to fight the Russo-Japanese War--obviously, not likely to come their way if they're fighting the US itself. They may be able to drive the US Asiatic Squadron away from the Philippines, but its unlikely they can pull off anything as smashing as Tsushima IOTL, and even if they can they have to do it two or three times more to deal with the fleet the US can bring to bear in less than a year. Much like the Two Ocean Navy in WWII, the navy the US is building is larger than the one they have in the water.
It's no WWII with unconditional surrender as the goal, but the war likely ends after a couple major fleet actions when Japan basically runs out of ships and the US is likewise running low, with a minor transfer of islands and increased US investment in Pacific fleet bases and coaling stations going into 1904. And, of course, if McKinley still gets assassinated...well, Teddy Roosevelt finally found his war.