Sen. Marco Rubio declared he would confront Vladimir Putin head-on if elected president, drawing an unstated, but sharp, contrast between himself and Donald Trump. “We are barreling toward a second Cold War, and strong American leadership is the only force capable of ensuring that peace and security once again prevail,” Rubio said, in prepared remarks he is expected to deliver at a national-security speech in Iowa on Friday. “The more our current president fails the test of leadership against Putin, the more important it becomes for our next president to pass it. I will pass this test.”

The Florida Republican and presidential candidate said his policy on Russia would involve providing lethal military assistance to Ukraine, sanctions against high-level Russian officials, and moves to isolate Russia diplomatically by ending engagement on issues unrelated to ending the crisis in Ukraine. “As soon as I take office, I will move quickly to increase pressure on Moscow. I will impose a new round of sanctions on the Kremlin’s senior leadership and other Russian entities, including Gazprom....”

Trump, on the other hand, has promised good relations with Putin.

“I will tell you that, in terms of leadership, [Putin’s] getting an ‘A’ and our president is not doing so well,” he said recently. In other comments, he has promised a “great relationship” with the Russian leader.

— Tim Mak