2 Have they ever met?
Apparently not, despite Trump's hints to that effect. In a 2013 tweet, Trump wondered if Putin might join him at a beauty pageant in Moscow and "become my new best friend". Though Putin didn't show, an associate of his, Vladimir Kozhin, did, and met Trump.
3 Why does this matter?
Though the Cold War is over, that face-off between the US and the Soviet Union still frames much of the world's military posture. That's why Trump's suggestion that he might not deploy the US military if Russia attacked a fellow member of the North Atlantic Treaty Organisation caused alarm throughout eastern Europe and drew condemnation even from Republicans. The suspected involvement of Russia in hacking and leaking emails and internal reports from the Democratic National Committee raises the equally alarming prospect that Russia is trying to meddle in an American election.
4 Was Russia really involved in the email hacking?
Hillary Clinton's campaign and some cybersecurity experts think so. The FBI is investigating, and Russia is said to be a leading suspect, though it denies any involvement.
5 What other ties are there?
Trump's campaign chairman, Paul Manafort, worked for Viktor Yanukovych, the former president of Ukraine, who was ousted from office in 2014 because of his closeness to Putin's Russia. Carter Page, an investment banker who is advising Trump on foreign policy, built a career on deals with Russia and its state-run gas company.
- Bloomberg