Katie Couric's Notebook: a New START

His name was Bert the Turtle. He was very smart, and knew what to do when danger was near - duck and cover.

That always-ready reptile was a symbol of the Cold War, which reached a boiling point in the 1950s. But by the late 1960s, cooler heads prevailed...and arms control negotiations between the U.S. and the Soviet Union led to the SALT treaty.

Now, 40 years later, the grandson of SALT...called New START...is on the table. President Obama and Russian President Dmitry Medvedev have already signed it, and today, five former secretaries of state have called for it to be ratified by the Senate.

The treaty, they argued, is a continuation of efforts both nations have made to reduce the threat of nuclear war...and they're urging Senate Republicans not to play politics with issues of national security.

While dangers still exist in the world...arms control made it safer for Bert the Turtle...to come out of his shell.

That's a page from my notebook.

I'm Katie Couric, CBS News.