Russia and Ukraine just turned much of the Black Sea into a dangerous no man's land

• Russia and Ukraine have exchanged threats this week to ships sailing through the Black Sea. 
• Both sides warned that they will consider any vessel in the area to be a carrier of military cargo and a legitimate target.
• A US official said Moscow has mined the water and may try to justify attacks on civilian ships. 

Russia and Ukraine threatened to militarize the Black Sea by warning they could target vessels sailing through the strategic body of water, a dangerous escalation that jeopardizes the safety of commercial vessels and risks drawing other nations into the bloody conflict.