The simplest way to neutralize the SCOTUS ruling:

[stellad]

http://www.unbossed.com/index.php?itemid=2797

... Congress should prohibit any corporation from engaging in this new political spending if it has any non-American shareholders or owners. Because after all, foreigners have no 1st Amendment protections.

The “logic” behind the SCOTUS ruling is that a corporation composed of individuals ought to possess the legal attributes of its individual owners. Thus the same logic ought to require that partial foreign ownership renders the corporation a foreign body at least in part. The foreign parts of a corporation have no constitutional right to free speech. And since there is no practical way to distinguish the legal rights of the parts from the rights of the whole corporation (that presumption underpins the SCOTUS ruling), then it’s impossible to give American constitutional rights to part of a corporation but withhold them from another part.

Hence it is constitutionally permissible to deny a partly foreign-owned corporation from spending on political speech within the United States. Congress should act to do so immediately.

Why make this a priority? There can’t be many large corporations that are entirely owned by American persons. Indeed large corporations would not find it easy to determine the legal status of their actual human owners (that’s the rotten core of the Supreme Court’s insistence on treating corporations as if they were homunculi, or composite persons). And it should be obvious that the last trade-off that corporations will want to make, in order to be able to interfere directly in political contests, is to drive away foreign investors.