Doyle McManus: What would a Republican president do about Ukraine?
Here's what the United States has done so far in an attempt to deter further Russian incursions into Ukraine: applied two rounds of economic sanctions and asked Congress to approve $1 billion in loan guarantees for Kiev.
Here's what President Obama says he won't do:
"We are not going to be getting into a military excursion in Ukraine," he told a television station in San Diego last week.