Brought on by the oft-discussed concept of the "Gutter Crown" offered to Fredrick William IV by the Frankfurt assembly of a united, liberal Germany, I've recently been exposed to the fact that in a way the Prussian King did actually attempt to spin the event into an earlier formation of the German Empire in his own, more conservative image in the form of the Erfurt Union. This shakey coalition of the Prussian state and democratic elements within Germany, while failing to entice pretty much any of the other major principalities into willingly joining and and lacked a strong domestic footing, it DID create enough of an impression to exploit the Republican revolution in Hesse, trigger a reaction in Austria and the Anti-Revolutionary states within the German Confederation, and would (if allowed to mature) have the backing of at least the main power brokers within the Prussian state. (Including, if the generals don't pull a conservative coup, its army).
Historically, William proved quite willing to throw his erstwhile allies under the bus and (until driven on and facilitated by the policies of Bismark) lay his ambitions of a united Germany under the rug. But what if, seeking to bring about his Imperial ambitions and confident he could both beat Austria and spin his actions into a reputation/political capital to head off the tide of demands for liberal reform that sought to undermine his throne and potentially rather other German states to his cause by refusing Russian mediation and marching his army into Hesse to "protect" its new government and integrate it into his Union? I can't imagine Austria would accept this lying down, especially after the knock to her reputation by the Revolution in Hungary and troubles she faced in Italy, and would invoke a federal intervention as head of the German Confederation.
It's late here, so I can't give the full play-by-play of how I personally think it'd play out quite yet, but here's some questions about this scenario that are worth considering.
1. Who's side, if either, would the other major German states such as Bavaria, Saxony, Hannover, ect. weigh in on? Bavaria is quite likely on Austria's side, but given the recent flare up of revolutionary fervor and the fear of reactionary crack-down by the Austrian regime could we see popular pressure, military threat, or statesmen believing they can maximize their retained power/privilege by backing Prussia now driving states to one side or the other.
2. What would be the international reaction to such a war? A conferance? Keeping the event an internal German affair? Intervention on Austria's side to put down Prussia's ambitions? Russia, as Austria's ally, seems most likely to intervene, but would France and Britain be willing to tolerate an expanded presence by Moscow's influence into the heart of centeral Europe?
3. Does Prussia have the military power to defeat Austria in such a war?
4. Assuming Prussia loses (Which I believe they would), what would the punishment be?