Well, this is a somewhat complicated question as it "blame" would insinuate that either side did something it ought not have done, which requires one to make a value judgement as to exactly how much of a "place in the sun" Germany was justified in seeking relative to its contemporaries (Britain and France, specifically). Personally, I'd say Britain's stubborness to try to maintain the intenational status quo/pre-German Unification balance of power certainly played a bigger role in the general escalation of international tensions, as it relegated Germany to a geopolitical-influence position increasingly misaligned with its actual economic and military importance. Take, for example, British concerns about German goods displacing British ones even in the domestic market; of course this was going to be the case if German industrial production was rising at a much higher clip than the pre-established colonial powers and she had no sphere of influence in which to 'vent' her excess production without bumping into pre-established interests. The naval race, too, was largely the result of Britain's strict aherance to an overwhelming dominance doctrine in terms of capital ships.
However, I don't BLAME Britain for any of the choices she made, as they were well in line with expected national interests (IE maintaining Pax Brittanica and the stability of her Empire, for which the bedrock was an unbeatable Royal Navy and domination of the sea lanes commerically)