Germany Should Not Have Invaded Belgium in WW1

Schlieffen Plan was formulated by the german high command as a way to knock France out of the war quickly by avoiding the fortified French border and striking through Belgium, however it was deeply flawed and rooted in outdated tactics. A better plan would have been to defend the border along Alsace Lorraine which was narrow and defensible and attempt to knock Russia out the war. When the Schlieffen plan was created it was made with the Franco-Prussian war in mind. The powerful Prussian artillery and given them a distinct edge when attacking French defensive positions, leading many military thinkers to favor offensive warfare. However, innovations in warfare such as the machine gun rendered this inference obsolete. It also doesn't take into account the rise of railroad infrastructure and the huge advantage it grants defenders. Railroads alow defenders to use internal lines far more effectively by shifting troops rapidly across fronts. France and Germany are two modern industrialized nations with professional armies and nationalist sentiments deeply ingrained in their society. This is also before the dawn of mechanized warfare, meaning it is very hard to exploit breakthroughs and encircle opposing forces like the Plan intended to do. This match up is pretty much a guaranteed stalemate. So what if the Plan somehow works and Paris falls? They have no hope of encircling their opponents, historically the French army used their railway system to redeploy their army to defend Paris very rapidly. If the Germans win the Battle of the Marine, they still have to siege Paris. Assaulting it is out of question as machine guns will dominate the city's urban choke-points. They will have to comit a large portion of troops to starving the city out giving the French time to regroup. Historically , the fact that Germany occupied parts of nothern France caused the French right wing and socialist parties to form a 'sacred union' were they put aside politics and focused on wining the war. I think that shows that the French will not simply capitulate. They even tried to carry on the Franco-Prussian war after having their main army captured and Paris besieged. If the Germans push farther south, they get repeated siege warfare at the very best, but most likely the offensive will slow down and some kind of trench warfare will set on. The Germans now have to worry about occupying a hostile country while also holding a massive defensive line. As the invasion of Belgium brings the British into the war, the Germans are now waging a war of attrition with their homeland under Royal Navy Blockade. They also have to deal with the Russians who are invading Prussia. Assuming the French tore up railroads while retreating, it's going to take a while to transfer forces to the eastern front to deal with that. By the way, this is what happens if the plan somehow succeeds far beyond it's historical achievements. Historical the Germans are forced into a war of attrition that they can't win as they are under blokade. In the east, the Russians become a major threat, effectivly destroying the Hapsburg army and invading East Prussia and Galacia. Historically, the Germans scored an extremely lucky victory at Tannenburg, however that doesn't change the fact that the lack of troops on the eastern is a major weakness of the Plan that was only resolved by the extreme luck of the German commanders. In short, attacking through Belgium puts the Germans in an unwinnable war of attrition that becomes less feasible if they don't anhilite the Russians at Tannenberg, as a failure to drive Russia from Prussia could lead to Austria being knocked out of the war before Germany can do anything about it. A far better plan would be to invade Russian Poland and stay on defensive in the west. It would be a similar situation to 1915 were Germany stayed on the defensive in the west while attacking in the east. Major differences being a smaller front, no Britain, no Blockade, no Sacred Union, and Germany can attack before the Russians fully deploy. The German border was hilly fortified terrain that would have been very hard to take. The British do not join the war and blockade Germany. It took the British and the French four years to break the western front against an enemy facing a blockade wearing down the home front. How is France supposed to break German lines alone, against defensible terrain, and without the blockade? Also the french army mutinied in 1917, refusing to fight a war to regain their own territory, how will French morale and political unity hold up when they are fighting a bloody war to take German territory? If the Germans attack the Russians, they can possibly destroy parts of the Russian army piecemeal as the russian army deployed far slower then the Germans. The Russian army would be thrown into panic and spend a good deal of time reorganizing . If Germany seizes Poland with little opposition it means that they prevent the huge defeats the Austrians suffer and also are in a good position going into 1915 as they can use the russian railway system to defend their captured territory.