What I find ridiculous are the arguments around victimization and retaliation. Poor British banks. The nasty Americans picks on them. The Americans are doing it even more. We should investigate their banks!
What I find irritating is the challenge to the legitimacy of capitalism is (still) perceived as a worry. The second worry on the fragmentation of the financial industry is hard to explain, and somewhat related to the first one, in that capitalism at its best only works well in the premises of the financial globalization.
The capitalism launched and pushed relentlessly since Reagan and Thatcher has demonstrated that the global flows of capital are as predictable and devastating as hurricanes. The patient economists which predicted that globalization of capital and elimination of its controls would bring in long-term, sustainable growth-producing FDIs and would help spread prosperity were so wrong. From the Asian Tigers crisis to the "innovative instruments" disaster and the sovereign panic, lightly touched (and taxed) capital has delivered instability, short term unequal gains and much larger long-term and much more unequal losses.
Most economies that did well have actually insulated from the fury of the hot money and prospered through trade of goods, which are much less globalized than capital. The proponents of "globalization" invoking free market principles and promising prosperity for the masses, raise nationalistic trade barriers and are the biggest critics of free movement of labor.
The real threat to jobs and growth is the continuation of New York and London banks dictating the distribution of global GDP and writing the rules of the game. And no rule applies to themselves.