The explosions in London have all the trademarks of Al Qaeda (search): Attacks on crowded trains and other hard-to-guard public places, an effort to wreak maximum chaos and a quick claim of responsibility.
The goal appears the same, also: To pressure countries with troops in Iraq to pull out.
Thursday's attack in London strongly resembled the string of bombings on four commuter trains in Madrid, Spain, that killed 191 people in March 2004. In that case, the bombs were placed in knapsacks on the trains.
In the London attacks, which killed dozens and wounded hundreds, there was no immediate sign that homicide attackers set off the blasts.
What lessons have American officials learned from the London attacks to keep our transit system as safe as possible? We'll ask Fran Townsend, White House Homeland Security adviser.
Plus, will the attacks strengthen the world's resolve to continue the War on Terror? Sens. Pat Roberts, R-Kan., and Chris Dodd, D-Conn., join the debate.
And, we'll get powerful political punditry from our panel of FOX News contributors: Charles Krauthammer, nationally syndicated columnist; Ceci Connolly of The Washington Post; Bill Kristol of The Weekly Standard, and Juan Williams of National Public Radio.