Bitcoin’s path to the grave has always been fairly clear to me. . . . You can’t seize a Bitcoin like you can seize a dollar, since it’s simply an alphanumeric string. But people need to be able to get their money in and out of the Bitcoin economy in order for it to be a useful alternative. With Mt. Gox and other Bitcoin go-betweens having such a hard time staying afloat, it probably won’t be long before even some Bitcoin diehards consider packing it in.