(CNN) Ex-presidents tend to recede from public view, particularly when they leave office -- as George W. Bush did -- with a Gallup approval rating hovering around 30%.

But Bush is returning to the national stage this week in the role of an elder statesman. He's promoting his new book "Portraits of Courage: A Commander in Chief's Tribute to America's Warriors" in television appearances and spoke before a sold-out crowd Wednesday evening at the Ronald Reagan Presidential Library in Simi Valley, California.

His return to the political scene comes as President Donald Trump's new administration is rocking Washington with upheaval and instability.

At the Reagan Library event, Bush made clear he did not want to second-guess the current President and said his comments this week had been misconstrued as criticism.

"I'm asked the question, 'Do I believe in free press?' And the answer is, absolutely I believe in free press," Bush said. "So I answered that question, and of course the headlines were 'Bush criticizes Trump.' And so therefore, I needed to say there should be a free and independent press, but it ought to be accurate."

Photos: Presidents of the United States Photos: Presidents of the United States George Washington was the first President of the United States, serving from 1789 to 1797. He also served as commander-in-chief of the Continental Army, and he has the distinction of being the only President unanimously elected by the Electoral College. Hide Caption 1 of 44 Photos: Presidents of the United States The second U.S. President, John Adams, served from 1797 to 1801. He was also the first vice president of the United States, and he was the first President to reside in the White House, moving in on November 1, 1800, while the White House was still under construction. Hide Caption 2 of 44 Photos: Presidents of the United States Thomas Jefferson, the third President (1801-1809), was the principal author of the Declaration of Independence. While President, Jefferson doubled the size of the United States by purchasing the Louisiana Territory from France in 1803. Hide Caption 3 of 44 Photos: Presidents of the United States James Madison, the fourth President (1809-1817), was nicknamed the "Father of the Constitution." During his presidency, the first formal declaration of war was enacted -- the War of 1812 with Great Britain. Hide Caption 4 of 44 Photos: Presidents of the United States James Monroe (1817-1825) was the last of the Founding Fathers to be elected President. During his seventh State of the Union address, he outlined a foreign policy that warned European powers against further colonization of or meddling in the Western Hemisphere. This was later known as the Monroe Doctrine. Hide Caption 5 of 44 Photos: Presidents of the United States John Quincy Adams (1825-1829) was the son of second President John Adams. He was the only President to serve in the House of Representatives after serving as President. Hide Caption 6 of 44 Photos: Presidents of the United States Andrew Jackson (1829-1837) was the only President to serve in both the American Revolution and the War of 1812. He is also the only President to have been a former prisoner of war: Jackson was 13 when became a courier during the Revolutionary War, and he was later captured by the British. Hide Caption 7 of 44 Photos: Presidents of the United States Martin Van Buren (1837-1841) was the first President to be born a U.S. citizen. Previous Presidents were born before the United States was a country, making them colonists and, consequently, citizens of Great Britain. Hide Caption 8 of 44 Photos: Presidents of the United States William Henry Harrison (1841) probably had only just finished unpacking his things at the White House when he died of pneumonia one month into his term. Harrison was the first U.S. President to die while in office, and he had the shortest tenure ever of any commander-in-chief. Hide Caption 9 of 44 Photos: Presidents of the United States John Tyler's term (1841-1845) saw several presidential firsts. He was the first vice president to succeed office after the President died, he was the first to lose his wife while in office, and he was the first to marry while in office. Hide Caption 10 of 44 Photos: Presidents of the United States James K. Polk (1845-1849) oversaw the greatest expansion of territory of any President in history. The expansion included what would become the future states of Texas and California. Polk also negotiated with Britain to establish the boundaries of the Oregon Country. Hide Caption 11 of 44 Photos: Presidents of the United States Zachary Taylor (1849-1850), aka "Old Rough and Ready," was a hero in the Mexican-American War. Mystery surrounds his actual cause of death from a stomach ailment. Did he just eat too many cherries, or was it murder? The 1991 exhumation of his body proved it wasn't arsenic poisoning at least. Hide Caption 12 of 44 Photos: Presidents of the United States Millard Fillmore (1850-1853) was the last President who was neither a Democrat or a Republican. He helped pass the Compromise of 1850, legislation that included the Fugitive Slave Act and California's admission to the Union as a free state. Hide Caption 13 of 44 Photos: Presidents of the United States Franklin Pierce (1853-1857) was the first President to not get his party's nomination for re-election. He signed the controversial Kansas-Nebraska Act, which allowed the people there to decide whether to allow slavery. This worsened the tension between the North and South. Hide Caption 14 of 44 Photos: Presidents of the United States James Buchanan (1857-1861) was the only President who never married. He failed to prevent seven pro-slavery states from seceding during his term. Hide Caption 15 of 44 Photos: Presidents of the United States Abraham Lincoln (1861-1865), purveyor of tall top hats and log cabins, preserved the Union during the Civil War and freed the slaves through the Emancipation Proclamation. He was assassinated by actor John Wilkes Booth, a Confederate sympathizer. Hide Caption 16 of 44 Photos: Presidents of the United States Andrew Johnson's (1865-1869) trial by impeachment in the U.S. Senate resulted in his acquittal by a single vote. History gives him a terrible performance review: His plan for post-war Reconstruction failed, and he had little support from Congress or the public. Hide Caption 17 of 44 Photos: Presidents of the United States Tasked with unifying the country after the Civil War, Ulysses S. Grant (1869-1877) established the Department of Justice to protect the rights of freed slaves. He also authorized the military to fight the Ku Klux Klan and successfully lobbied for the 15th Amendment, granting voting rights to black men. Hide Caption 18 of 44 Photos: Presidents of the United States Rutherford B. Hayes (1877-1881) promoted women's rights, signing legislation that allowed female lawyers to argue Supreme Court cases. He introduced the White House Easter Egg Roll as a spring tradition and established the first presidential library. Hide Caption 19 of 44 Photos: Presidents of the United States Just four months into his term, James Garfield (1881) was shot by a disgruntled lawyer who'd aspired to join the administration as a diplomat. The President was taken to the Jersey Shore, where doctors hoped the ocean air would help him recover. He died two weeks later. Hide Caption 20 of 44 Photos: Presidents of the United States Chester Arthur (1881-1885) signed a bill mandating a merit-based system for hiring public workers. The idea was to curb patronage and politically motivated appointments. Hide Caption 21 of 44 Photos: Presidents of the United States Grover Cleveland (1885-1889; 1893-1897) was the first and only commander-in-chief to serve two non-consecutive terms. He was also the first bachelor President to be married at the White House. Hide Caption 22 of 44 Photos: Presidents of the United States Benjamin Harrison (1889-1893) signed into law the Sherman Antitrust Act of 1890, which authorized the government to fine large corporations for price fixing and other corrupt business practices. Hide Caption 23 of 44 Photos: Presidents of the United States William McKinley (1897-1901) led the country through the Spanish-American War, a three-month conflict that began with the sinking of the USS Maine and ended with Cuban independence. During the beginning of McKinley's second term, he was fatally shot by an anarchist. Hide Caption 24 of 44 Photos: Presidents of the United States At 42, Theodore Roosevelt (1901-1909) was the youngest man to take the oath of office. A progressive reformer and environmental advocate, Roosevelt brought lawsuits against corporate trusts, taking on business giants to level the playing field for the working class. Hide Caption 25 of 44 Photos: Presidents of the United States William Howard Taft (1909-1913) also served as the Chief Justice of the U.S. Supreme Court in his post-presidency years. During his re-election bid, he managed to win only eight of 531 electoral votes -- the poorest performance of an incumbent president seeking re-election. Hide Caption 26 of 44 Photos: Presidents of the United States Woodrow Wilson (1913-1921) was awarded the 1919 Nobel Peace Prize for proposing and creating the League of Nations. But he was never able to convince the United States to join. Although he was first opposed to a federal amendment allowing women to vote, Wilson shifted his position during his second term and the 19th Amendment was ratified in 1920. Hide Caption 27 of 44 Photos: Presidents of the United States Warren G. Harding's term (1921-1923) was cut short by his sudden death from a cerebral hemorrage. Harding captured 60% of the popular vote in 1920, marking the largest presidential landslide to date. Hide Caption 28 of 44 Photos: Presidents of the United States Calvin Coolidge (1923-1929) served as vice president until the death of Warren G. Harding. His 1924 campaign slogan was "Keep Cool with Coolidge," and his nickname was "Silent Cal" because of his reputation as a man of few words. Hide Caption 29 of 44 Photos: Presidents of the United States Herbert Hoover (1929-1933) was inaugurated on the year of the stock market crash that sent the country into the Great Depression. Although Hoover pushed for money to be appropriated for large-scale projects, he opposed federal relief payments directly to individuals. The national economy never recovered during his term, and the shantytowns that developed were nicknamed "Hoovervilles." Hide Caption 30 of 44 Photos: Presidents of the United States Franklin D. Roosevelt (1933-1945) was the only President elected to the office four times. During his 12 years as President, he championed numerous social programs and measures, including the creation of the Tennessee Valley Authority, the Civilian Conservation Corps and Social Security. Roosevelt contracted polio at age 39 and never recovered the use of his legs. Hide Caption 31 of 44 Photos: Presidents of the United States Harry S. Truman (1945-1953) served as vice president for 82 days before the unexpected death of Roosevelt. He authorized the use of two atomic bombs on the Japanese cities of Hiroshima and Nagasaki. Hide Caption 32 of 44 Photos: Presidents of the United States Dwight D. Eisenhower (1953-1961) had been supreme commander of the European Allied forces during World War II, and he ordered the Normandy invasion on D-Day. His popular presidential campaign slogan was "I like Ike!" Hide Caption 33 of 44 Photos: Presidents of the United States John F. Kennedy (1961-1963) was the first Roman Catholic President. He was assassinated in his first term, which was marked by the signing of the Nuclear Test-Ban Treaty, the creation of the Peace Corps, the disastrous Bay of Pigs invasion, and the beginning of military involvement in Vietnam. Hide Caption 34 of 44 Photos: Presidents of the United States Lyndon B. Johnson (1963-1969) was vice president under John F. Kennedy and took the oath of office on a plane after Kennedy was assassinated. In 1964, Johnson signed the Civil Rights Act, the landmark legislation that banned segregation and discrimination based on race and gender. The law was a cornerstone of Johnson's vision of a "Great Society" that also included a "war on poverty." Hide Caption 35 of 44 Photos: Presidents of the United States Richard Nixon (1969-1974) became the first President to resign from office as he faced impeachment for his involvement in the Watergate scandal. Nixon made strides in domestic policy, proposing legislation that resulted in the Occupational Safety and Health Administration and the Environmental Protection Agency. Abroad, he established relations with China and a détente in Soviet relations. Hide Caption 36 of 44 Photos: Presidents of the United States Gerald Ford (1974-1977) had been appointed vice president by Nixon after Spiro Agnew was forced to resign. He then became President when Nixon himself resigned. Remembered mainly for his pardon of Nixon and his physical clumsiness, Ford was not elected to a second term. Hide Caption 37 of 44 Photos: Presidents of the United States Jimmy Carter (1977-1981) brokered the 1978 Camp David Accords, the agreement that led to a peace treaty between Israel and Egypt. At home, Carter's presidency was plagued by inflation and unemployment, and he lost his bid for a second term amid the hostage crisis in Iran. Hide Caption 38 of 44 Photos: Presidents of the United States Ronald Reagan (1981-1989) was the only actor ever elected President, and his talent as a speaker earned him the moniker "the great communicator." An affable Republican who wooed many Roosevelt Democrats, the staunchly anti-communist Reagan is seen as having played a large part in the collapse of the Soviet Union. Hide Caption 39 of 44 Photos: Presidents of the United States George H.W. Bush (1989-1993) was a former CIA director and served two terms as vice president under Ronald Reagan. His approval rating at home soared after he led an international coalition to oust Iraq from Kuwait, and communism in Eastern Europe fell on his watch. But he lost his bid for re-election amid a sluggish economy and after reneging on a promise not to raise taxes. Hide Caption 40 of 44 Photos: Presidents of the United States Bill Clinton (1993-2001) ran on the slogan, "It's the economy, stupid." Plagued by various scandals -- including accusations of sexual impropriety -- he was the second president to be impeached. He was acquitted in 1999. Hide Caption 41 of 44 Photos: Presidents of the United States George W. Bush (2001-2009) is the son of former President George H.W. Bush. His presidency was largely defined by his response to the 9/11 terrorist attacks. In 2003, he ordered the invasion of Iraq on suspicion that Saddam Hussein had weapons of mass destruction. Hide Caption 42 of 44 Photos: Presidents of the United States Barack Obama (2009-2017) became the first African-American to hold the office of President. He took the oath of office amid the Great Recession, the biggest economic challenge since the Great Depression. Under the Affordable Healthcare Act, millions of uninsured Americans have gotten health insurance. Hide Caption 43 of 44 Photos: Presidents of the United States Real estate mogul and reality television star Donald Trump was sworn into office in 2017. His slogan "Make America Great Again," became the central theme of his campaign. Hide Caption 44 of 44

Nevertheless, Bush's presence underscores the contrast in tone between the two most recent Republican presidents and serves as a reminder of how the expectations surrounding presidential rhetoric and tone have changed over the years.

Bush "was a president who after 9/11 talked about Islam as a religion of peace," said Steve Schmidt, a Republican strategist and former Bush aide. "He talked about the act of illegal immigration -- people who took great risk coming across the desert -- as an act of love for their families."

"All presidents have been in difficult times and divisive fights, but there was a normalcy of behavior expected of the American head of state rhetorically," Schmidt said.

He cited the recent example of Trump blaming generals for the loss of Senior Chief Petty Officer William "Ryan" Owens during a covert mission in Yemen. ("They lost Ryan," Trump said in an interview with Fox News that aired Tuesday).

"That's not how George W. Bush, or Barack Obama, or Bill Clinton, or George Herbert Walker Bush, or Ronald Reagan talked about the military," Schmidt said. "He was a president who served in turbulent times and was controversial, but as is always the case -- when a president has distance from their presidency, voters look at them and are much more likely to see their virtues than their flaws."

Trump tempered his tone -- at least temporarily -- with a strong performance at Tuesday's joint address to Congress. The emotional high point of his speech came when he spoke directly to Owens' wife, Carryn, who watched the speech from the first lady's box.

Photos: President Trump's first address to Congress Photos: President Trump's first address to Congress US President Donald Trump addresses a joint session of Congress for the first time on Tuesday, February 28. Behind him, from left, are Vice President Mike Pence and House Speaker Paul Ryan. Hide Caption 1 of 22 Photos: President Trump's first address to Congress Trump speaks at the beginning of his address. Hide Caption 2 of 22 Photos: President Trump's first address to Congress A wide view of the House chamber. Hide Caption 3 of 22 Photos: President Trump's first address to Congress Supreme Court justices watch the speech. From left, in front, are John Roberts, Anthony Kennedy, Stephen Breyer, Sonia Sotomayor and Elena Kagan. Hide Caption 4 of 22 Photos: President Trump's first address to Congress Maureen Scalia, the widow of late Supreme Court Justice Antonin Scalia, is applauded during the speech. Hide Caption 5 of 22 Photos: President Trump's first address to Congress Carryn Owens, center, cries as she is applauded by the chamber during Trump's speech. Owens' husband, Navy SEAL William "Ryan" Owens, recently was killed during a mission in Yemen. "Ryan died as he lived: a warrior and a hero, battling against terrorism and securing our nation," Trump said. The applause lasted over a minute, which Trump said must be a record. Hide Caption 6 of 22 Photos: President Trump's first address to Congress Trump also recognized Megan Crowley, a college student who, at 15 months old, was diagnosed with Pompe disease and wasn't expected to live past age 5. Her father founded a pharmaceutical company to find a cure. "Megan's story is about the unbounded power of a father's love for a daughter," Trump said. "But our slow and burdensome approval process at the Food and Drug Administration keeps too many advances, like the one that saved Megan's life, from reaching those in need." Hide Caption 7 of 22 Photos: President Trump's first address to Congress Muslim activist Fauzia Rizvi, a guest of US Rep. Mark Takano, watches Trump's address. Hide Caption 8 of 22 Photos: President Trump's first address to Congress Members of Trump's Cabinet applaud the President. From left are Defense Secretary James Mattis, Education Secretary Betsy DeVos, Attorney General Jeff Sessions, Treasury Secretary Steve Mnuchin and Secretary of State Rex Tillerson. Hide Caption 9 of 22 Photos: President Trump's first address to Congress Trump smiles during his speech, which lasted over an hour. Hide Caption 10 of 22 Photos: President Trump's first address to Congress House Minority Leader Nancy Pelosi listens to the speech. Hide Caption 11 of 22 Photos: President Trump's first address to Congress The President waves before starting his speech. Hide Caption 12 of 22 Photos: President Trump's first address to Congress Trump is applauded after arriving in the House chamber. Hide Caption 13 of 22 Photos: President Trump's first address to Congress Trump shakes hands with Ryan before starting. Hide Caption 14 of 22 Photos: President Trump's first address to Congress Trump shakes hands on his way through the chamber. Facing the President here are Health and Human Services Secretary Tom Price, left, and UN Ambassador Nikki Haley. Hide Caption 15 of 22 Photos: President Trump's first address to Congress Trump stands in the doorway of the House chamber while being introduced. Hide Caption 16 of 22 Photos: President Trump's first address to Congress Pence confers with Ryan before Trump's speech. Hide Caption 17 of 22 Photos: President Trump's first address to Congress First lady Melania Trump, bottom right, is applauded as she arrives in the chamber. Hide Caption 18 of 22 Photos: President Trump's first address to Congress US Sen. John McCain, left, talks with US Sen. Lindsey Graham before Trump arrived. Hide Caption 19 of 22 Photos: President Trump's first address to Congress US Sens. Cory Booker and Bob Menendez arrive in the House chamber. Hide Caption 20 of 22 Photos: President Trump's first address to Congress Many Democrats wore white as a nod to the women's suffrage movement. Posing for a photo here are, from left, US Reps. Brenda Lawrence, Joyce Beatty, Marcia Fudge and Val Demings. Hide Caption 21 of 22 Photos: President Trump's first address to Congress US Sen. Bernie Sanders arrives for the speech. Hide Caption 22 of 22

He also spoke in more measured terms about race and the need for the country to unify even as he maintained hardline positions on issues such as building a wall along the US border with Mexico and repealing and replacing Obamacare.

On the news interview circuit this week, Bush has been peppered with questions about Trump's controversial actions on immigration and his targeted travel ban (which was halted by the federal courts).

Bush, whose brother Jeb was hazed by Trump during the Republican primaries, never warmed to Trump in the general election. In interviews this week, he has been careful to avoid personal criticism Trump, but made his displeasure clear about both the political climate and some of the President's policies.

"I don't like the racism, and I don't like the name-calling, and I don't like the people feeling alienated," Bush told People Magazine. "Nobody likes that."

Bush took issue with Trump's characterization of the press as the enemy.

"I considered the media to be indispensible to democracy, that we need an independent media to hold people like me to account," Bush said on NBC's "Today" earlier this week. "Power can be very addictive, and it can be corrosive, and it's important for the media to call to account people who abuse their power, whether it be here or elsewhere."

During an interview with "Sunday Today" host Willie Geist, Bush also seemed to make the case for the so-called "Dreamers," who were brought to America as young children, to stay in this country.

"I think somebody who has vested time and effort and can make a contribution to our country will be a really good citizen," the former President told Geist. "See in Texas, we grew up with a lot of people of Hispanic heritage and we're used to the contributions they have made to our state and to our country."

At the same time, he acknowledged the political difficulty in finding compromise on changes to the immigration system.

"I tried to reform it and one of my big regrets was that I couldn't get Congress to respond," he said. "And I think the plan I laid out ultimately would be the plan that would be accepted."