Published: Sep 02, 2014 6:12 AM EDT
Updated: Sep 02, 2014 10:17 AM EDT

WASHINGTON- With the Ukrainian crisis firmly in the forefront, President Barack Obama heads for Estonia today on his way to this week's NATO summit, amid criticism that he's being too tentative in the face of global threats.
    
The crisis between Russia and Ukraine has raised the stakes at the summit. Obama will press member states to increase their defense spending.