Paul Ryan's big night: What did we learn

Mitt Romney's running mate Paul Ryan energized the GOP convention Wednesday with a conservative speech that led with attacks against President Barack Obama.

CNN's Tom Cohen is OutFront with five things we learned from the conventions second night:

1. Romney's enforcer comes to play

On Tuesday, the GOP convention was about love (Ann Romney) and respect (Chris Christie).

But to the chagrin of head-scratching Republicans eager to take the fight to President Barack Obama, there wasn't much talk in the Tampa Bay Times Forum about the current administration in Washington.

Paul Ryan put those anxieties to rest on Wednesday with a lengthy, aggressive and systematic attack on Obama's record in office, with one question as the thesis: "Without a change in leadership, why would the next four years be any different from the last four years?

FULL POST