The US focus on the Atlantic was taking Cuba, and concern about the Spanish Fleet raiding/attacking the US east coast. It was not about seizing the Canary Islands (of no value in themselves and not on the way to anywhere), and Africa was never happening. had the Spanish not sued for peace there was discussion of the US Fleet bombarding Spanish ports, but that never really had any traction as by the time the US Fleet was done with supporting Cuban efforts and eliminating the Spanish naval threat to the US (and this was way overblown) the war was over.
It took the Oregon, an almost brand new battleship, 66 days to go from San Francisco to join the North Atlantic Squadron. For the Asiatic Fleet, or significant elements of it, to go from the Chinese coast to the Eastern Atlantic to be useful for an assault of the Canaries for example, would have taken much, much longer. The logistic requirements for coaling, food, etc that would need to be made would be huge, and dealing with maintenance would be a nightmare. Just look at the Russian experience in 1905. If the Asiatic Fleet is not dealing with Spanish possessions in the Pacific, it is most certainly not dealing with anything in the Atlantic. In any case, once the US fleet has dealt with the Spanish fleet at Santiago, Cuba, the US forces already in the Caribbean/Atlantic are more than adequate to deal with whatever the US wants to do in the Atlantic if the war goes on as the Spanish Navy is now reduced to very little indeed.
Even if the USA wants to grab Spanish possessions in the Atlantic, the US MUST deal with Cuba and Puerto Rico first, so you need to postulate a totally insane Spanish government that having lost Cuba, Puerto Rico, and much of its navy, decides to fight on with no allies. Not that even if the USA does not grab Guam and the PI, germany, Japan, and the British all have desires.