I saw it. For a fictional docu-drama it was good. It takes one whopper of a suspension of disbelief for anyone to believe that early 20th century weaponry could successfully repel aliens who had mastered interstellar travel. Shit most scientists today think our modern military would be crushed by invading aliens.
Oh and the magic metal liquid which they reverse engineer at a time when electricity was barely available to the general public - forget the name - plus infected horses wins the war. [roll eyes]
Outside of that, was OK.
There is no suggestion that the invaders had mastered interstellar travel. If in fact they were from Mars, they only needed limited interplanetary travel. Admittedly it is left a bit vague where the aliens actually originated. Humans took to calling them Martians only because they noticed an explosion on Mars shortly before the arrival of the meteor that hit Germany. Of course, even at high speed it actually takes months for something other than light to reah Earth from Mars...so who knows.
My only real quibble with the docudrama was the fact that 2013, as presented, looked nearly identical to our own. Yet, even ignoring the technological advances that should have come from reverse engineering alien technology...politically the world should look very different without a defeated Germany and no justifiable reason for the mass revolt in Russia that led to the creation of the Soviet Union.
Additionally, it made little sense that the US stayed out of the war for several years. While the US in 1913 was not the power that it would be later in the century, it was still a great power by any reasonable measure. European powers warring with eachother, though tragic, has happened before and thus it was reasonable for the US to consider being "neutral" in WWI. An alien invasion is an existential threat to everyone equally. What possible reason would the US have for saying, lets sit back and wait for the world's first line of defense to fall so that we can face the possibility of facing the threat alone?