Washington (CNN) -- Robert Dole knew his share of Washington fights -- as the Republican vice presidential and presidential nominee and as both Senate majority and minority leader.
But as he celebrates his 90th birthday on Monday, he told CNN he believes the tone in Washington is much more bitter -- and that is not helping the country.
"There were a lot of differences in the days I was in the Senate," he told CNN in a rare interview. "But in every case we were able to work the out the differences."
Dole served in the Senate alongside several Democratic leaders who were known for their strong wills: Robert Byrd, George Mitchell and Tom Daschle.
"We disagreed, but we respected each other," he said. "We never had an unkind word about each other."
Now as Dole looks at today's Congress he thinks the two parties are not doing enough to try to find a middle ground -- and that includes relying too much on the filibuster in the Senate.
"It is very frustrating. Sometimes it is just justified, don't misunderstand me. But most of the time you ought to be able to work out a compromise that is going to be voted on," Dole told CNN. "Compromise has become a bad word, and I always thought in almost every case there is room for compromise."
Senate leaders should change how they use the filibuster, he said.
"There are things that should be stopped, but at least there ought to be a vote," he said. "It can't continue, this constant holding up bills."
As for what else is causing some of the rancor today, he told CNN "the biggest problem today is the lack of trust." Asked who is to blame for that, he put responsibility on both parties -- "Sometimes it is the Rs (Republicans). Sometimes it is the Ds (Democrats)."
Just last week Senate Majority Leader Harry Reid, D-Nevada, threatened a historic change regarding the rules of how presidential nominations are considered -- eliminate the ability to filibuster them if Republicans didn't allow votes on several of the president's picks. If those changes would have gone into effect, the atmosphere in Washington would have deteriorated even more. But even the threat of the rules change created a war of words between Reid and Senate Minority Leader Mitch McConnell, R-Kentucky.
This week the Senate is expected to consider a bipartisan compromise to help cap student loan rates -- a politically popular idea. But senators were able to reach agreement only after weeks of partisan haggling, several failed attempts and the intervention of President Barack Obama.
Dole also sees major problems in how far his party has shifted to the right, saying a moderate from a conservative state will face problems because of "some who don't believe they are Republican enough."
He repeated a statement he originally made in May in a television interview as a sign of how rigid the party has become, saying, "that is why I said that Ronald Reagan I doubt could be nominated today. And I was a conservative and supported Reagan."
Dole, who was the GOP's 1996 presidential nominee, losing to incumbent Bill Clinton, urged his party to do a better job of trying to be more inclusive.
"I believe we ought to be reaching out to the Hispanic community, the black community and of course the middle- and upper-class community across the board, and we haven't done that," he said, pointing to the last election as evidence.
After having served eight years in the House of Representatives, he began his first term in the Senate in 1969 and served there until 1996, when he resigned to concentrate on his run for the presidency after capturing the Republican nomination.
He was Gerald Ford's running mate in 1976 when Ford lost to Jimmy Carter.
Since his time in Congress the Kansan native, the longest-serving Republican leader in the Senate, has seen a dramatic change in those serving and their goals.
"A lot of the younger members -- they are very smart. They are very capable. They have their own ideas -- start a filibuster, rather than compromise."
He cited how food stamps was added to the farm bill in the past as key to attracting support for the measure in both parties. The House earlier this month passed a scaled-down farm bill without food stamps after a version including them was defeated because it could not attract a large enough coalition.
Dole, who is disabled from a World War II injury, also was disappointed last December after some of some of his own personal lobbying failed. The Senate blocked ratification of a United Nations treaty to promote the rights of disabled people. Dole, in a wheelchair, came to the Senate floor in a last ditch effort to help the treaty gain support.
As for his successes, he cited the 1990 Americans with Disabilities Act as one of the bills he was most proud of because of its lasting impact and one that had bipartisan support. He was also a major fundraiser in helping get the World War II Memorial built on the National Mall.
Dole, who is special counsel in the Washington law firm of Alston & Bird's legislative and public policy group, spends his time with his wife, former Sen. Elizabeth Dole, in Washington but is mostly out of public view. He is a co-founder of the Bipartisan Policy Center and works to support a political institute named in in his honor at the University of Kansas.
Dole has suffered from several illnesses in recent years, and spent 11 months at Walter Reed Army Hospital in 2010 after a bout with pneumonia.
President George W. Bush appointed Dole in 2007 to a panel investigating conditions at the hospital.
"I never really thought I wanted to spend that much time there," he joked at a 2011 appearance honoring the 50th anniversary of his being first elected to Congress.
Asked about the milestone of his 90th birthday, Dole said "It's going to be a special day. I don't know how many people reach 90," adding "I am kind of excited about it."
Many friends and old staff members will gather Tuesday for a party celebrating his special day.