ALEXANDER NEMENOV/AFP/Getty Images
Armed men in military armed block access to a Ukrainian border guards base not far from the village of Perevalne near Simferopol on March 3, 2014.
Washington is facing a tough foreign policy challenge now that Russia has escalated the conflict in Ukraine by seizing control of the country's strategic Crimean peninsula.
There are concerns that Russian president Vladimir Putin might go even further and send Russian troops to Russian-speaking regions of Ukraine, sparking even more hostilities.
Ukraine has been struggling with a violent conflict that overthrew the president, Viktor Yanukovych, and killed at least 88 people. Washington is now faced with how to respond to the escalation. Neither Washington or other world leaders are considering a military response but Secretary of State John Kerry called Putin’s move into Ukraine "an incredible act of aggression."
Yesterday, Kerry outlined some possible international repercussions for Russia that included possible visa bans and economic sanctions. Kerry is scheduled to leave tonight for a trip to Ukraine to meet with the transitional government and the Ukrainian people.
What should the American response be to Russia's military invasion of Ukraine? How can the US make it clear to Russia that there will be global consequences? Should the response be purely economic?
Matt Rojansky, Kennan Institute Director at the Wilson Center and former Deputy Director of the Russia and Eurasia Program at the Carnegie Endowment for International Peace
Christian Caryl, Washington-based senior fellow at the Legatum Institute, described as an independent public policy organisation advancing ideas and policies in support of free and prosperous societies and contributing editor of Foreign Policy magazine.