Mitt Romney’s selection of Paul Ryan as his running mate for the American presidency confirms that this campaign is going to be mainly about domestic issues — barring a not-impossible Israeli attack on Iran between here and there. It is likely to count for zero that is intelligent concerning American foreign policy during the next administration. Yet foreign affairs will be the most important issue of all to address as the United States staggers forward into the void.

Instead, the campaign may be expected to obsessively deal with the clashing economic and tax ideologies and shibboleths that have driven the Republican Party debate, and that have, under Republican administrations, driven the nation itself deeper into deficit and debt, ever since Ronald Reagan laid his blessing upon the teachings that ever-lower taxes on the rich produce ever-higher tax income for governments, that the dynamism of a nation is produced by market competition unfettered by regulation or government (or excessive attention to law), and that the social needs of society are best met by private enterprises working for competitive profit advantage. Entrepreneurs are a race of heroes, and their critics are the kind of people responsible for the socialist shackles under which Americans struggled from 1932 until their liberation by Dwight Eisenhower’s inauguration to the presidency in 1953. (And even Eisenhower remains a dubious figure to believing Republicans, tainted by his formation in the socialist environment of the old Regular Army and a professional lifetime spent dealing with foreigners abroad.)

Abroad will have need to look after itself if the Romney/Ryan ticket is elected, which might prove a good thing for all concerned were national debt and the daze of domestic dispute to distract a new administration from global adventure — something earlier generations of Republicans were traditionally disposed to leave to the Democrats.

However, the party of national isolation from a corrupting world has in recent decades been under neo-conservative foreign policy management, and belligerent in outlook (“Don’t Tread on Me!” has been the tea party’s battle flag proclamation, borrowed from the American Revolution). The party’s policy leadership has been globalist, a legacy to the neo-conservatives from Trotskyist permanent revolution: the world lies open to be remade, although now by American revolutionary ideology, rather than that of Stalin’s rival and victim.

Neither Mitt Romney nor Paul Ryan seem close to the hawkish ideology that gave the United States its present military deployments in Asia and Central Asia, and now increasingly in Africa. But they seem to have no clear intellectual position at all, which is to say that they might easily become the instruments of others with aggressive ideologies of their own. Certainly the Netanyahu government in Israel counts far more on the Republicans than on Barack Obama to endorse or reinforce any Israeli attack on Iran, and Mr. Romney himself has announced that in his mind Jerusalem already belongs whole and entire to Israel.

His attention to the Arab awakening and even to civil war in Syria has been perfunctory at best. However, he and his colleagues would certainly back to the hilt the spirit of militarism now in possession of the Pentagon, with the endorsement of the Obama Democrats, expressed in a January 2012 policy statement that reiterated the universal military doctrine that America must permanently be stronger than all possible American rivals combined. As Andrew Bacevich has said on the subject of American statecraft and strategy, “Washington has become an intellectual dead zone.”

For his part, President Obama seems to have nominated himself strategist in chief of the new American war against bandits, highway men, kidnappers, political rebels and troublemakers in the wastes of the Sahara and the Horn of Africa, as well as the thankless task of building nations in Sudan and Somalia. This in addition to his personally running what amounts to a new American international Murder Incorporated, looking for bad guys to kill, of which there are all too many. Possibly there are better and more constructive tasks for him to undertake.

Visit William Pfaff’s website for more on his latest book, “The Irony of Manifest Destiny: The Tragedy of America’s Foreign Policy” (Walker & Co., $25), at www.williampfaff.com.