President Barack Obama’s call for “meaningful action” following one of the deadliest mass shootings in American history — and one of the most shocking, with 20 children killed — is likely to face a tough road in Congress and in the lobbying circles that influence it.

“What’s he going to do? He’s not going to get legislation,” said Larry Sabato, a political science professor at the University of Virginia. “That’s obvious to anybody.”

Sabato and other experts predicted that Washington’s powerful gun lobby — and the many lawmakers from both parties who are cognizant of its influence — virtually assures the failure of any legislation aimed at curbing gun rights. At best, Sabato said, Obama could try other policy approaches in an attempt to improve public safety, such as by backing legislation that would require more metal detectors in schools and other public places. …

Many Democrats also stopped short of calling for policy changes, instead saying that Friday was “a day for mourning the loss of the victims and for coming together as Americans,” as Rep. Allyson Y. Schwartz, D-Pa., put it in a statement.