Briefing

'Dear friends, I am pleased to get in touch with you through Twitter. Thank you for your generous response. I bless all of you from my heart.'

1. POPE BENEDICT XVI, using the Twitter handle @Pontifex, on Dec. 12 in his first tweet

'What they're really talking about is giving you the right to work for less money.'

2. PRESIDENT OBAMA, at a Michigan auto plant, railing against a new right-to-work law that reduces the clout of organized labor in the traditionally pro-union state

'The campaign is already on.'

3. SILVIO BERLUSCONI, former Italian Prime Minister who resigned amid scandal last...