The crime of treason is defined in 18 U.S. Code § 2381.
But, more importantly, it seems to be lost on you that the Constitution was written in 1789, and there have been a LOT of court decisions concerning what the words in it mean.
But nowhere in there does it say "declared war" or legally defined "enemy".
It likewise doesn't say "airplane" and yet the federal government operates an Air Force and the FAA.
Perhaps, if you are not finding a definition of a word of interest to you in the Constitution, you might turn your attention to, say, relevant decisions issued by courts in the last 200 years and change - and which other courts will apply if asked.
It's not as if court cases are decided on the basis of smoking a doobie, sitting back, and then free associating on what the words might mean.
And, if you actually bothered to embark on that exercise, you would indeed find the occasional instances in which someone was tried for treason and in which the
WORDS WERE DEFINED.
For example try this one on for size:
United States v. McWilliams, 54 F. Supp. 791 (D.D.C. 1944)
Now, before even digging into the case, note that it was decided in 1944, which was an interesting time to be accused of aiding an enemy.
McWilliams was a Nazi:
First, the indictment avers that there began in Germany in 1933 a movement to substitute for the existing form of government in the United States a National Socialist form by causing insubordination, disloyalty, mutiny, and refusal of duty by members of the military and naval forces of the United States; that the thirty defendants named in the indictment joined in such movement; and that on June 28, 1940 Congress made it a crime (without regard to wartime or the use of force) for anyone "with intent to interfere with, impair and influence the loyalty, morale and discipline of the military and naval forces of the United States" to "advise, counsel, urge and cause insubordination, disloyalty, mutiny and refusal of duty by members of the military and naval forces of the United States," or to "distribute and cause to be distributed written and printed matter advising, counseling and urging insubordination," etc., as aforesaid (18 U.S.C.A. § 9), or to conspire to commit any of the said prohibited acts (18 U.S.C.A. § 11).
Second, the indictment charges that continuously from and after June 28, 1940, and up to and including the date of the filing of this indictment, and in continuance of the aforesaid movement in which they had joined, the thirty defendants, in violation of said law, conspired in the District of Columbia with one another and with officials of the German Reich and leaders and members of the Nazi Party therein, as co-conspirators; and that as a part of said conspiracy and as means and methods of accomplishing the objects thereof, the said defendants and co-conspirators did, in the District of Columbia, (a) cause to be printed and circulated, inter alia, 42 specified publications and (b) use, inter alia, 35 specified agencies as distributors, and (c) thereby and otherwise disseminate, inter alia, 24 specified representations and charges.
Okay, he was working with the Nazis since 1940.
However...
The averments as to what happened between 1933 and 1940 cannot be deemed a charge of conspiracy to commit treason (18 U.S. C.A. § 1) since an essential element therein is aid and comfort to "enemies" and Germany did not become a statutory enemy until December 1941.
So, at least one court, the US District Court for the District of Columbia, disagrees with you.
Do you have a court that agrees with your interpretation?
This was a US court, in 1944, saying that an honest-to-Betsy Nazi could not be prosecuted for treason for acts in which he engaged until war was declared in December 1941.
This decision was issued in February 1944 - the first month that Allied troops set foot on Japanese territory - and this court could not say that promoting Nazism to US troops was treason prior to December 1941.
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