The still-shaky economy rightly remains the top issue in this year’s presidential campaign. But foreign policy is also important. And Mitt Romney presented a positive, sweeping agenda for America’s international relations Monday in a major speech at the Virginia Military Institute.

In some cases, the specific policies the Republican nominee presented didn’t offer a wide contrast with those of President Barack Obama. For instance, Mr. Romney echoed the president’s Afghanistan-exit timetable, explaining: “I will pursue a real and successful transition to Afghan security forces by the end of 2014.”

Yet Mr. Romney’s tone was distinctly more assertive of America’s traditional global-leadership role. Sounding a familiar theme, he warned that “if America does not lead, others will — others who do not share our interests or values.”

He stressed the importance of keeping the U.S. Armed Forces strong. As he pointed out in last week’s debate on domestic issues, even current Secretary of Defense Leon Panetta has raised an alarm about the president’s planned military-spending cuts.

And Mr. Romney said he would take a tougher line against Iran’s nuclear ambitions and Syria’s brutal repression of an ongoing rebellion.

He fairly criticized the incumbent: “I know the president hopes for a safer, freer and a more prosperous Middle East allied with the United States. I share this hope. But hope is not a strategy. We cannot support our friends and defeat our enemies in the Middle East when our words are not backed up by deeds, when our defense spending is being arbitrarily and deeply cut, when we have no trade agenda to speak of, and the perception of our strategy is not one of partnership, but of passivity.”

The Obama campaign responded with a new commercial that called Mr. Romney’s foreign-policy positions “reckless” and “amateurish” — and cited his “gaffe-filled” European tour in July.

However, the most prominent of those alleged “gaffes” were Mr. Romney’s reasonable expression of concern about security at the London Olympics and his citing of cultural differences as a reason that Israelis have fared better economically than Palestinians.

Yes, the Romney campaign did initially overstep in the immediate aftermath of Sept. 11 violence against U.S. diplomatic sites in the Mideast by issuing a statement accusing the administration of showing “sympathy to those who waged” them.

But the Obama team was irresponsibly slow to acknowledge that those were orchestrated terror attacks and not merely spontaneous protests against an anti-Muslim movie trailer on YouTube.

And as Mr. Romney correctly said Monday: “The attacks on America last month should not be seen as random acts. They are expressions of a larger struggle that is playing out across the broader Middle East — a region that is now in the midst of the most profound upheaval in a century.”

He added that the West’s ongoing conflict with the forces of Islamic radical terror is “a struggle between liberty and tyranny, justice and oppression, hope and despair.”

And: “The first purpose of a strong military is to prevent war.”

Of course, it’s much easier to find fault with a commander in chief than it is to be one. Certainly Mr. Obama should have learned that lesson by now with his emphasis on diplomacy yielding such disappointing results.

And while Mr. Romney’s promise to maintain a military powerful enough to deter —and if needed, defeat — threats to international stability sound reassuring, his plan also sounds quite expensive.

The tabs for playing world cop aren’t confined to monetary measure, either. Americans are justifiably war weary — and wary of future military missions that would cost us not just U.S. treasure but U.S. lives.

Mr. Romney — and the president — should address those concerns in their final two debates on Oct. 16 and Oct. 22. So should Rep. Paul Ryan and Vice President Joe Biden in their debate Thursday night.

The struggling economy is still Americans’ No. 1 concern, but voters need more details from the two tickets on why, where and how they would exert U.S. power.