There That was no terrorist attack, they just returned to sender a lot of stuff, all at once. The terrorist attack was the humans delivering an exploding ball by suicide bomber...
It was obvious from the start of the first episode that this was related to the Dr. Who IP (the mention of UNIT in the first five minutes). I initially didn't have those expectations of this miniseries, but whit that my expectations changed drastically. No matter the budget, Dr.Who and related IP (like Torchwood), always have a certain style to them, I would call 'distinctly British'... Just like so many UK series tend(ed) to be so different from US productions. Just as the Swedish series also have a distinct style...
It's not bad. Sure, they could have done more in less time. I'm waiting for the last episode, but it could be that the end of the miniseries IS the start of the war between land and sea. Or it's the figurative 'war' between land and sea that was pretty much represented by all the garbage that was returned to sender...
EDIT: Mumbles something about lack of sleep...