The attitude of France in that final showdown, which all could see approaching by 1860, would be crucial. No one could predict which way Napoleon III might choose to lean, or whether he might even directly intervene once an Austro-Prussian War began. He might just take the opportunity to carve out more gains for France at the expense of Germany, whether united without Austria, as Prussia wanted, or still under the thumb of Austria, should the Hapsburgs win. And with the Germans fighting it out among themselves, who could stop the battle-tested and well-armed French Army from doing what they chose?
The French abolished their monarchy for the second time in 1848 and wrote themselves yet another constitution. However, finding the turmoil of what began to look like a return to resurgent Jacobinism (now wearing a Socialist costume with newly-minted Marxist credentials licking its heels) too much to stomach, in 1850 the voters elected the Second Republic’s First (and only) President in the person of non other than Louis-Napoleon Bonaparte, the nephew of the Great One!