Envelopes recently addressed to the president and sent to the Pentagon, thought to contain ricin, remind us of the deadly potential of biological threats. I received a similar letter, containing anthrax, 17 years ago. Despite some progress, significant gaps obviously still remain in our nation's ability to defend against biological attacks and such naturally occurring diseases as Ebola.

America was still recovering from the Sept. 11 terrorist attacks when white-powder letters arrived at the U.S. Capitol and media companies in Florida and New York, killing five and infecting 17 others. It was a frightening and uncertain time.

The bipartisan Blue Ribbon Study Panel on Biodefense (of which I am a member) recently convened leaders in Washington to revisit the 2001 anthrax attacks and other biological incidents. The panel asked how far our country has come since those events and what else the nation needs to do. Unfortunately, the list is long.

For me, this is very personal. For the nation, it is absolutely critical.

Some nation-states and terrorist organizations are actively seeking to develop or obtain biological weapons to attack the United States and its interests overseas. Others are conducting dual-use research that could be used to help or harm, such as recent research synthesizing horsepox that indicated the same could be done for any poxvirus, including smallpox. And the outbreaks and spread of diseases such as Zika and Ebola also show how unprepared we remain for naturally occurring outbreaks and pandemics. Our ability to respond is not keeping pace with the increasing biological threat.

One recent positive development is the White House's release of a National Biodefense Strategy several weeks ago. The production and implementation of a comprehensive national biodefense strategy were among the top recommendations of the panel's 2015 National Blueprint for Biodefense.

The new strategy addresses the full spectrum of activities that make up biodefense – prevention, deterrence, preparedness, detection and surveillance, response, attribution, recovery, and mitigation. With it, we have taken an important step forward as a nation to address natural, accidental, and intentional biological events.

But a strategy is just the beginning. Now the hard work of implementing the strategy starts. Work and timelines must be assigned to specific federal departments and agencies in a public and transparent way. Just as important, Congress must also adequately fund these departments and agencies, which for too long have had too few resources to sufficiently prepare for and respond to biological threats.

I will never forget my first interview with the FBI in the days immediately after the anthrax letters arrived. I asked investigators what their confidence level was that they would find those responsible. They answered, "100 percent."  In 2010, nine years after the attack, the FBI, Department of Justice, and U.S. Postal Inspection Service concluded that scientist Bruce Ivins, alone, was responsible for those anthrax letters. However, further review by independent scientists concluded that Ivins could have been the perpetrator, but the science on its own could not prove it. I hope that our response to similar events in 2018 and beyond will lead to more definitive answers.

When our nation faced enormous challenges 17 years ago, Republicans and Democrats took action, together. They tried to better prepare our country with Project BioShield and other programs. Unfortunately, many of those efforts were not sustained. If we do not act swiftly now to shore up our biodefense, the price we pay will be measured in American lives.

Former U.S. Senate Majority Leader Tom Daschle serves on the bipartisan Blue Ribbon Study Panel on Biodefense. He is the founder and CEO of the Daschle Group, a strategic advisory firm.