I'm skeptical. The international "Left" is toothless. It now primarily consists of: the bureaucratic power elite who profit from and broker activity in a top/down economic spoils and patronage system; the idle and affluent young who have adopted pagan or secular belief systems to rebel against their health, prosperity and well-being; the mostly insane intelligensia and gentry class. You know the cast of characters from the Seattle and Genoa protests: Daddy's little headstrong girl from Monterey; the angry son of a CEO from Skokie or Bridgeport; the trust fund malcontents from Bonn, Venice or Stockholm. Bored rich kids looking to get laid, bored rich and tenured intellectuals, greedy gatekeepers of tax receipts. Boredom or lust for money, that's what it comes down to with the "Left" in our world today.
Even the most ardent ALF or anti-capitalist adherent, however, isn't strapping on a corset of dynamite and blowing himself/herself to bits in service to their greater cause. That's one of the things about being a secular acolyte, dying has no upside.
That's the sole purview of the religious zealots. Islamic these days. They are medieval butchers and ignorant soldiers of martyrdom, and they scare EVERYONE! The European left just chooses to pretend they don't really live in THEIR countries, among them - and even if they do: "they're really only mad at the U.S. and Israel, and so are we, we swear! Please?!!!!"
The Brits get it, the Russkies get it, the Turks get it, so do the Scandanavians and the ever dependable Aussies. The Germans and French are infested with these bad guys, and they're paralyzed in fear and leaderless dishonor. Radical Islamism is a dynamic, lethal and dangerously compelling force of violent upheval - the International "Left" are merely useful infidels and idiots they will exploit before they are to be killed too.