What if: Spanish-America War of 1873

America has been making some moves for Luzon like corporations entering the settlement, they might buy Luzon in their peace settlement, then get Formosa.

how good were the american ships in 1873. Once i read that the US navy quickly was outdated, but it is only a few years after 1865.
How good were the spanish ironclads? If they are superior the US navy is helpless - because these ships were - at last on paper vastly superior to anything "normal" in that time. But i have no clue about the spanish ships.

the spaniards for sure would be pushed into problems, the USA was much stronger economically, but how many people do they want to loose for an island?
Also, what would other european countries do? As far as i understood that time, lots of US politics thought quite interesting (in the sense - our gods send right to take this or that island), if this or that are british or french islands, things could be - well interesting.

i think in the 70ties of the 19th century was the last time european nations could have beaten the USA in a war.
So, if the french or british navy is drawn in (on spanish side) the USA face a huge problem.

The U.S. would win, thanks to the internal disorders of Spain at this time, and annex Cuba but Cuba alone due to limited power projections at this time. This probably would also have the effect of engendering a Carlist Spain, as a result of the conflict.

Overall, I think the war would last longer, but the US would likely win in the end. I think the former Confederates operating in Cuba, along with this Virginius, would give Spain a good reason to go to war with the US. But I think it would go something like this:

1873-10 - Virginius affair occurs, Spain declares war on the United States.
1873-11 - Spanish ships in Cuba sail for Florida, and attack Fort Jefferson at Dry Tortugas, and Fort De Soto at Tampa Bay, barely being forced off. The US begins a program to build up its naval fleet and modernization. Financially, with over 2 billion in debt from the Civil War, and the issue of paper money Greenbacks still floating around, the US is not in the best situation, but the war causes an earlier end to the plundering occurring due to Reconstruction. Southern states begin to be readmitted to the Union faster, and rights of former Confederates restored quicker, and federal troops begin withdrawing from the South. As the states are readmitted, former Confederate soldiers begin taking the Union uniforms and signing up for the navy beside their former enemies.
1874-01-04 - southern railroad begins being rebuilt so that troop movements can be faster, and farms and homes are rebuilt to support troops, increasing the food production capacity of the south much faster than OTL. Troop training and armaments flow south, and by April, new semi-iron-clad ships with more cannons are setting sail with steam/sail propulsion to Cuba, and from California to the Philippines and Guam and the Northern Mariana Islands. Southern blacks sign up to fight, and end up fighting alongside southerners in battles in the war.
1874-04 to 08 - Several naval battles off the eastern seaboard, Cuba, Puerto Rico, and the Philippines occur. The Mariana Islands fall in their entirety to a small three ship squadron to the United States.
1874-05 - Americans land at Guantanamo and along the northern coast of Cuba. Americans fight with the Cubans to oust the Spanish, and begin fighting northward to Havana, while the Navy keeps Havana occupied, under siege, and unable to send reinforcements southward.
1874-09 - Puerto Rico's capital, San Juan, falls to the US troops.
1874-10 - the Philippines fall to the United States after four months of fighting for the capital.
1875-03 - American troops along with Cubans finally oust Spain from the island of Cuba.
1875-05 - US and Spain sign treaty ceding Cuba, Puerto Rico, the Mariana Islands, and the Philippines to the USA. Fighting together in the US causes the two sections to grow closer together, easing some of the hard feelings of the last war. Another effect is the quicker return of the south to Congress, quicker restoration of southern infrastructure and capital. Black disenfranchisement still happens, as the Republicans were using their votes to maintain power in Congress, and Democrats in the South still disenfranchise them, and continue the black codes Republicans instituted in the South while under their control. Cuba becomes a US protectorate and the other islands become territories. US troops scale back, while ex-Confederates who are less eager to live in the US move to Puerto Rico and Cuba, hoping to maintain their 'way of life' there.
1876 - Republicans still win the White House, but Democrats take the House, and start rolling back some of the laws and graft of the Grant administration, but still have to contend with a Republican Senate.
1877-07 - Spain again launches an attack, this time with refit forces, and sails to attack Havana. Landings target Cubans, and the second Spanish-American War begins.
1878-02 - Having barely demobilized, the US had a large pool of available Army, Navy, and Marines, already seasoned from the last war, and finally defeat Spain again. Cuba is made a territory and is put on the path to statehood, as is Puerto Rico, and additional movement from the continent to the islands brings them further into the US culturally. Internal US politics result in southern repeals of some black codes under Garfield's administration in exchange for more money spent in the south to repair their infrastructure. Southern blacks still can't vote, but their freedom of movement and economic opportunities improve, and the path to true civil rights comes sooner than the 1960s.
1898 - Cuba becomes a state
1904 - Puerto Rico becomes a state.

That could be a way it could go.

The idea of that ironclad in Brooklyn blasting away at the Brooklyn Naval Yard, Manhattan and whatever else in sight is quite something!
IIRC, I read once about there being effective naval guns at The Narrows (between Staten Island and Long Island) so they might sink the ship on its way out... though that depends if they were there in 1873.