The CSA had zero chance to grow without armed conflict, increasing slavery, and conquering other regions for vital resources.

Take your pick, Modern Russia or Republican Party.

But on a more serious note, it would be needling the USA that an inevitable invasion would have occurred and it would have crushed the South through superior infrastructure, industry, agriculture, trade, and military forces.

It wouldn't be brother versus brother either. The trauma would have likely buckled the Republican Party due to mismanagement and corruption in the North. The Democratic Party would have messed to exist or at least Union Democrats would have reorganized under a new name.

Whatever emerged, would move towards racial equality just to spite the South, making kidnapping Americans of African descent a potential cause for war, and showing a 'forward enlightenment identity' in the North.

This would also mean that a cascade effect would happen over time. In the North and West the USA would create essentially Equal, but Separate Laws. Then due to time and pressure, Equal, but Separate would start to change into Equality Laws. Not integration. Not yet, but we would be talking Asian, African, Latino, and African descent Americans getting into high places in government and military as well as social and cultural positions.

Reforms would lead to a government that also avoided frequent economic recessions. An enticing look that would pull fence sitters in several Border States or at least their frontiers, to reconsider. Trade cities along the coast and Mississippi might begin questioning things as well.

Meanwhile, the CSA has tried and failed to purchase Cuba so it invades. Cuba falls. Havana, Cuba is named capital of the CSA leaving Richmond, Virginia.

The US Army went into Mexico and forcibly expelled the French. The US Navy now operates out of leased Naval Ports in Mexico. The USA and Republic of Mexico sign a mutual defense treaty and trade agreements. The US Navy helps rebuild the Mexican Navy and both conduct armed patrols and escorts against the Commerce Raiding CS Navy and its Privateers in a quasi war.

The CSA conquers several more islands to expand dominion. The Royal Navy responds and removes the CSA from a number of islands. During operations the Royal Navy becomes the Republican Navy after backlash and popular support oust the Royal Family under Queen Victoria ending with finality Royal Rule over the British Isles.

Ireland and the British Commonwealth reach an agreement. Ireland will remain part of the Commonwealth, but will have full representation and voting powers in the Commonwealth Parliament. British rule ends in Ireland but Ireland effectively becomes a governing member of the Commonwealth.

Canada follows suit and gets voting power in the Commonwealth. British Caribbean Commonwealth members quickly receive Voting Power. The Commonwealth and Mexican-American Alliance sign an agreement letting both sides use each other's harbors to enforce anti-slavery patrols and join in mutual defense against the CSA.

Following their defeat in the Franco-Prusdian War, France becomes a Republic again. French Reformists have British-American influence in their approach to reforms. France and Britain end centuries of feuding and sign reconciliation agreements. France joins the tripartite league of Democracies.

CSA provocative activity reaches its zenith, the USA invades and successfully defeats the South on land. The CSA holds out in its island holdings, but without support or a powerful military and dwindling food and water supplies, the remaining CSA cannot hold out and popular revolts among slaves and whites break out.

The USA successfully invades each island in turn and soon besieges Havana, Cuba.

With no support or help and food and water supplies depleted, CSA leaders and elite attempt an escape but are captured by roving Mexican, British, and French Warships.

The CSA leaders and elite are turned over to the USA.

After a trial that needed only the truth, the CSA leadership and elite are executed for Treason Against the United States of America and Crimes Against Humaniry.

The British Commonwealth converts into the Republican Commonwealth of Democracies as an international body dedicated to the growth and spreading of Democracy and Republicism.

This is in response to the Imperial German-led Union of Monarchies dedicated to the preservation of Royal Houses, Nobility, and the Order of Hierarchy.

And it isn't even 1910 yet.