Sorta but not really.

It should be, but pieces of paper are just dead trees with some dark colored stuff on them.

I mean, if it were actually the case that the constitution is what grants the government its power, then the government would have to follow the constitution, and it doesn't really -- at all.

I don't recall the part of the constitution that lets them regulate education, or to provide healthcare or social security, to fund Food and agriculture, science, housing, to fund building the civilian Internet, to regulate many of the things it regulates, to fund building an interstate highway system, and so on. There's some very specific phrases in the constitution that have been abused to hell and back to justify it, but none of that was ever what the federal government in the united states was supposed to do according to the founders.

The whole point of the united states was supposed to be more like the EU, and for most of history it was. Starting with Abraham Lincoln's dictatorial reign (sometimes dictators do good obviously in this case) presidents took a more active role in governing the country. World War 2 and the great depression had a further massive impact on increasing the role of the federal government in governing the country, and when the supreme court was about to step in because the new laws weren't legal, FDR threatened to pack the supreme court, so they accepted novel and ridiculous interpretations of the constitution.

If the founders intended to let congress create whatever laws they wanted, they wouldn't have specifically described the copyright and patent systems and the post office in the constitution. If Federal powers didn't need to be described in the constitution, then the federal government wouldn't have needed to pass a constitutional amendment to make alcohol illegal federally, and then later passed another amendment to take away that power.

The 10th amendment specifically lays out that powers not enumerated to the federal government don't get to stay with the federal government, but go to the states, and barring that to the people. "The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people." -- And the 9th also says that people's rights are much broader than just the rights enumerated in the constitution: "The enumeration in the Constitution, of certain rights, shall not be construed to deny or disparage others retained by the people."

Two of the most major debates of the moment, regulating the Internet, and gun control, are explicitly disallowed by the constitution, but instead of proposing a constitutional amendment, they're going to just do it anyway, and they do it anyway. That's the reality of how the federal government works today, they completely disregard the document that supposedly gives them their power.

So at the end of the day the political establishment has proven beyond any reasonable doubt that the constitution is just a piece of paper, and it will be disregarded the moment that it is expedient to do so.