It's been almost 15 years since about 3,000 people were killed in the deadliest terrorist attack on record. And in the years since Sept. 11, 2001, the U.S. government has undertaken a variety of measures designed to prevent further terrorist attacks.

In the "war on terror," Americans launched two full-fledged ground wars and engaged in many other military acts designed to wipe out al-Qaeda and other terrorist networks. Meanwhile, U.S. homeland security was reorganized at great effort and enormous expense — American taxpayers have contributed perhaps as much as $1 trillion to these domestic efforts alone.

But do Americans feel any safer? New polling data from the Chicago Council on Global Affairs gives us a resoundingly clear answer.

No, Americans do not feel safer. And they seem to have little hope that that will change anytime soon.

The Chicago Council found that 42 percent of Americans feel that their country is less safe than it was before Sept. 11, 2001 — compared with 27 percent in a 2014 survey. And almost nine out of 10 (89 percent) argued that terrorism was at least somewhat likely to be a part of life in the future. While this was the first time that the Chicago Council had asked this question, a lower percentage — 75 percent — said the same in a 2013 poll conducted by the Pew Research Center.

More than 2,000 adults were interviewed between June 10 and June 27, 2016, for the Chicago Council poll, with margins of error of 2.2 to 3.5 points depending on the question and higher margins of error for partisan subgroups. The Chicago Council has released a number of reports on the results of this survey recently, including in-depth looks at the views of supporters of both Hillary Clinton and Donald Trump.

The new data released by the Chicago Council is especially topical, given the widespread discussion of terrorism during the 2016 election campaign. Trump has repeatedly accused his Democratic rival of making America more vulnerable to terrorist attacks, even labeling her the "co-founder" of the Islamic State, an extremist organization that has orchestrated or inspired many attacks around the world.

Meanwhile, Clinton has hit back against Trump, suggesting that the businessman and political newcomer's provocative rhetoric only inflames the problem.

The Chicago Council found that no matter their political allegiance, Americans were deeply concerned about terrorism. Out of a range of possible threats to the United States, clear majorities of both self-identified Republicans (83 percent) and Democrats (74 percent) listed terrorism as a fundamental threat. In total, 75 percent of Americans viewed terrorism as a critical threat, more than any other listed threat and its highest percentage in a Chicago Council poll since 2004.

However, there was a split between the parties in the assessment of the threat of Islamist fundamentalism. Seventy-five percent of Republicans said it was a critical threat, while 49 percent of Democrats did. This was the highest number for Republicans on this issue in a Chicago Council poll since 1998 — higher even than immediately after the Sept. 11 attacks. For Democrats, the number was the highest since 2002. Overall, 59 percent of Americans viewed it as a fundamental threat.

It is important to note that a shooting at an Orlando nightclub that left 49 people dead occurred as the poll was being conducted. The shooting has been described as the deadliest terrorist attack on U.S. soil since 9/11. The attacker, Omar Mateen, pledged allegiance to the Islamic State during the attack; he was killed in a shootout with police. The Chicago Council noted that there was a shift in the poll responses after the attack: The mass shooting seemed to cause a four-percentage-point increase in the number of people who viewed international terrorism as a critical threat and a 12-percentage-point jump in those who felt that Islamist fundamentalism is a threat.

These increases may signify that the growing concern about terrorism and Islamist fundamentalism may have been a visceral reaction to the Orlando shooting. It's unclear whether the effects are short-term or long-term.

When it comes to how to fight terrorism, there is some common ground between Republicans and Democrats. Majorities in both parties (78 percent overall) say that blocking terrorist financing is the most effective tactic the United States has at its disposal. Supporters of both parties also say that using airstrikes or Special Operations forces to target terrorist groups was effective. Sixty percent of Americans say that sending U.S. combat troops to fight terrorists is effective, though there is a considerable split between Republicans (72 percent) and Democrats (57 percent).

There are some tactics that Republicans favor and Democrats oppose, however. Seventy-nine percent of Republicans favor limiting the flow of refugees and migrants and imposing stricter border controls, while just 44 percent of Democrats do. Overall, a small majority of Americans, 57 percent, are in favor of such a policy.

Meanwhile, the one tactic that Americans don't think is effective is torture. Overall, just 45 percent say that torturing terrorism suspects is a tactic that can work. That figure drops to 33 percent when we look only at Democrats, but a firm majority of Republicans — 64 percent — want to leave torture on the table.

More on WorldViews: