She has consented thus to consider the matter in doubt, and to leave to a foreign arbitration that which she believes fully admits of no doubt. The Government of the United States has declined this manner of settlement, resorted to by all nations in similar cases, when she should ought to adopt it, if she believes that reason and right is on her side. (Source: The New York Times, 3 Dec 1860)
Can we use, at least in some cases, two modals when we want to express possibility and obligation at the same time? Is this the reason why "should ought" is used in the piece above?