Liz Halloran

Freshman Sen. Rand Paul insists that he won't decide until next year whether a 2016 presidential run is in his future.

But comments the Kentucky Tea Party Republican made this week at a newsmaker breakfast about a run — "we're considering it" — as well as upcoming speaking engagements in early caucus and primary states Iowa and New Hampshire suggest serious consideration.

We have imagined ourselves searching like Kelly Manning for loved ones after the explosions on Boylston Street.

We have pictured ourselves huddling in the basement like Beth and Paul Robinson and their four children as bullets and bombs fly on our own city street.

Updated 1:50 p.m. ET: (Correcting that brothers shared an apartment in Cambridge, not Watertown.)

The suspects in Monday's deadly Boston Marathon explosions and the Thursday night murder of a police officer at the Massachusetts Institute of Technology are two brothers from a former Soviet republic who were in the United States legally for years, and lived together in a Cambridge, Mass., apartment.

Bipartisan bonhomie broke out Thursday afternoon when four Democratic and four Republican senators made a case for their comprehensive immigration overhaul proposal.

The scene at the Dirksen Senate Office Building stood in marked contrast to the ugly end Wednesday of a smaller cross-party effort to fashion gun legislation that would have expanded background checks and banned assault-style weapons.

As investigators combed through evidence in the deadly Boston Marathon bombings, seeking both motive and perpetrator, we turned Tuesday to a security expert for guidance on how the investigation may be unfolding.

Bryan Cunningham, a former CIA officer, assistant U.S. attorney and deputy legal adviser for the National Security Council, served in both the Clinton and George W. Bush administrations. He is now a senior adviser at the consulting firm the Chertoff Group, co-founded by former Homeland Security Director Michael Chertoff.

Rand Paul going to one of the top historically black colleges in the U.S. and trying to school students on who founded the NAACP?

Priceless.

Rand Paul going to one of the top historically black colleges in the U.S. and trying to make a case for his Republican Party as a historic and continuing defender of the civil rights of African-Americans?

Not boring.

And, judging from the reaction the Kentucky senator received Wednesday at Washington's Howard University, less than persuasive.

Thousands of supporters will descend on the U.S. Capitol on Wednesday to call for legislation that creates a path to citizenship for immigrants in the country illegally.

Sound familiar?

But this time, unlike in 2007 and 2010 when immigration legislation died in Congress after similar demonstrations, proponents of an overhaul say politics has swung inexorably toward their side.

"I've been working on this issue for more than a decade, and it feels unstoppable now," says Ana Avendano, director of immigration and community action at the AFL-CIO.

President Obama's campaign for new federal gun control laws takes him to Colorado on Wednesday, and next week back to Connecticut, where the Sandy Hook Elementary School massacre renewed the nation's fraught conversation about guns.

Two county prosecutors fatally shot in Texas. Colorado's top prison official gunned down. And a dozen more members of the U.S. justice community — ranging from police to judges — victims of targeted killings since the beginning of the decade.

What's going on?

The U.S. Supreme Court heard arguments Wednesday in a challenge to the 1996 Defense of Marriage Act, which defines marriage as between "one man and one woman as husband and wife."

It was the court's second and final day of hearing appeals involving same-sex marriage laws. And it served up some memorable observations from the high court denizens.

Justice Ruth Bader Ginsburg characterized same-sex unions under DOMA, which limits federal spousal benefits to heterosexual couples, as the equivalent of "skim milk" marriages.